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Animals were of prime importance in the classical world: agriculture in the Roman Empire depended on domesticated oxen (L., bos) to plow the fields, crowds of thousands cheered on the races at the Circus Maximus, as drivers atop their chariots urged on the fastest horses (L., equus) in the land, and sacrifices of sheep (L., ovis), and pigs (L., porcus) were necessary to please the gods. So too were animals important to ancient scientists and physicians. It was the dissection of and the experiments on animals that formed the basis for early understanding of human anatomy and physiology. In addition, there are countless anatomic terms whose etymologies derive from the Greek and Latin names of animals.

Cauda equina
Origin: Latin, cauda (tail) + equus (horse)
Horse’s tail

cauda equina

Sitting within and protected by the vertebral column, the spinal cord consists of nerve cells and their extensive myelinated tracts that carry motor, sensory, and autonomic data to and from the brain. One would think that the spinal cord extends all the way to the bottom of the vertebral column, but in fact it stops looking like a cord at the level of the L2 vertebra in adults. At that point, it gives rise to the so-called cauda equina where individual nerves arising from the lower part of the spinal cord descend down the vertebral column until they exit through the proper foramina. It’s no wonder then why lumbar punctures must be done below L2: the individual nerves of the cauda equina can easily accommodate the lumbar puncture needle unlike the large-diameter spinal cord. So the next time you consent a patient for an LP, be sure to ask yea or neigh.

Coccyx
Origin: Greek, kokkux (cuckoo)

sacrum

The vertebral column consists of seven cervical, twelve thoracic, and five lumbar vertebrae. The primary role of these bones is to protect the spinal cord. However, their articulations allow flexion, extension, lateral motion, and rotation of the back, explaining their derivation from vertere (L., to turn). There are two more bones that lie below L5. The sacrum, which the Romans called the os sacrum (L., sacred bone) and which the Greeks named the hieron osteon (Gk., sacred bone), sits within the pelvis and allows the sacral nerves of the cauda equina to exit through its foramina. It’s not clear why this bone was considered “sacred.” One thought is that its sacredness derives from its location in the pelvis and therefore an association with reproduction. Another theory suggests that the ancients used this bone during sacrificial ceremonies. Finally, below the sacrum sits the coccyx, the small bony remnant of a vestigial tail. The ancient anatomists who named this bone thought that, when viewed from its side, it bears resemblance to a cuckoo’s beak.

Tragus
Origin: Greek, tragos (goat)

traigus

The tragus is that small piece of cartilaginous tissue situated next to the opening of the ear canal. And for some strange reason, it’s derived from the Greek word for goat. Perhaps some Greek anatomist had particularly hairy ears and thought it resembled the hair on a goat’s chin. Whatever the reason, the association with goats definitely stuck: the medical term describing hair on the ears is barbula hirci, literally meaning “little beard of the goat” [L., barbus (beard) + hircus (goat)]. No kidding.

Concha
Origin: Greek, konkhe (mussel, shell)

concha

Within the nose lie the superior, middle, and inferior nasal conchae. These long shelves of bone on the lateral aspects of the nasal cavity are covered with mucosa and supplied by a rich network of blood vessels. Their most important function is to warm and humidify the air as it passes from the nasal cavity to the lungs. If I look really hard, I can make myself believe they look like little mussels. Astute readers will notice that concha also appears in the labeled anatomy of the outer ear: concha also describes the fossa next to the opening to the ear canal.

Pes Anserinus
Origin: Latin, pes (foot) + anser (goose)
Goose’s foot

pes anserinus

Three muscles of the leg, the gracilis [L., gracilis (slender)], sartorius [L., sartor (tailor)], and semitendinosus [L., semi (half) + tendere (to stretch)], give rise to tendons that travel in parallel before attaching to the same location on the tibia. The ancient anatomists who saw this arrangement must have been reminded of the tripartite webbed feet of the goose and named it as such. There is a clinical condition called “pes anserinus pain syndrome,” also known as “pes anserine bursitis,” that describes pain around these tendons on the medial side of the knee. Interestingly enough, pes anserinus is not only a structure in the leg: it also is another name for the parotid plexus, where the facial nerve branches after exiting the stylomastoid foramen.

Recurrent Laryngeal Nerve

galen dissection

Galen demonstrating the effects of the recurrent laryngeal nerve during the dissection of a pig

The recurrent laryngeal nerves are branches of the vagus nerves that control nearly all of the intrinsic muscles of the voice box. Therefore, injury to one or both may cause hoarseness or even a complete inability to phonate. The etymology is nothing to write home about, but the story of their discovery definitely is. The famed Greek physician Galen, while conducting an experiment on a live, strapped-down pig, accidentally cut both laryngeal nerves; the pig continued to struggle but completely stopped squealing. He ultimately traced out the path of the nerves and confirmed that they originated from the vagus nerves. He noted that “there is a hairlike pair [of nerves] in the muscles of the larynx on both left and right, which if ligated or cut render the animal speechless without damaging either its life or functional activity.” Galen held a public demonstration of his experiment in Rome that was well-attended by distinguished politicians and scholars of the time. Those readers interested in learning more can read the article “Galen and the Squealing Pig,” linked here.

Thanks for taking a trip to the zoo with me. I’m off to see the capybara exhibit.

P.S.: Can you think of the English adjectives derived from the Latin words mentioned in the first paragraph? As a bonus, what about the adjective that describe wolves? Fish? Ducks?

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Pneumonia is one of those medical conditions that is constantly thrown around without being rigorously defined—and as we all know by now, rigor is absolutely paramount in my view of academic medicine and medical etymology. Let’s start by looking at the word from an etymological standpoint:

Pneumonia
Origin: Greek, pneumon (lung) + –ia (condition of)
Condition of the lung

Well, that certainly wasn’t very helpful—at least not at first glance. There can be many conditions of the lung that are called “pneumonia” and the classic case of a lung infection is merely one of them. Compare pneumonia to pneumonitis:

Pneumonitis
Origin: Greek, pneumon (lung) + -itis (inflammation of)
Inflammation of the lung

There are many inflammatory conditions of the lung, but only a few of them are called “pneumonitis” because pneumonitis is considered to be inflammation of the lung tissue itself (the lung parenchyma). There are some who then consider pneumonia to be inflammation of the air sacs in the lungs (the alveoli). This makes sense for the most part; the bacteria, viruses, fungi, and parasites that can cause pneumonia would cause alveolar inflammation.

lung diagram

To put things in perspective, when somebody is admitted to the hospital for pneumonia, the classic picture is someone who acquires a bug, and said bug colonizes the alveolar space. The resulting “mass” that forms (usually in one lobe of the lung) is called a consolidation:

Consolidation
Origin: Latin, con- (with) + solidus (solid)
With solid, i.e., things that aggregate to form a “solid”

For these “classic” pneumonias, we can call them community-acquired pneumonia (CAP), hospital-acquired pneumonia (HAP), and the like. Some bugs associated with the former are things like Streptococcus pneumonia and Pseudomonas aeruginosa, and some bugs associated with the latter are things like Staphylococcus aureus and Haemophilus influenzae. (Stay posted for microbiological etymology!)

But it turns out that this isn’t the whole picture. Pneumonia is indeed as general as its etymology suggests, for there can be inflammatory and fibrotic conditions of the lung—and both classes can fall under the term “pneumonia.” (Generally, inflammation is caused by the infiltration of white blood cells and fibrosis is caused by the production of excess connective tissue, e.g., collagen.) Thus, as a counterexample to the definition that pneumonia is simply the inflammation of the alveoli, we have something called usual interstitial pneumonia (UIP). It is a form of interstitial lung disease in which the tissue between the alveoli is fibrosed with collagen.

uip ctThe classic “honeycomb lung” appearance of UIP on CT scan

To end this post, I posit my generalized definition of pneumonia: pneumonia is a principally inflammatory or fibrotic condition of the lung. By formalizing this definition of pneumonia, I am faithful to the etymology and make pneumonitis a subset of pneumonia. Note that I use the word “principally” in front of inflammatory—the reason why is that cancers of the lung can cause inflammation, but cancers are not considered to be pneumonias by any definition or practice.

In another post I will discuss the classic methods of diagnosing “normal” (generally bacterial) pneumonia and the etymologies of these techniques. Here is a small teaser: one of the terms involves the Greek word for goat! Can you guess which one? Leave a comment below.

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Playing the singular/plural game is always fun (at least to me), so here is a short aside with a few of my favorites that relate to the topics I lectured on these past few weeks:

  1. Apparatus → apparatus
    Origin: Latin, ap- (toward) + parare (to set)
    A piece of equipment, i.e., something that “sets you toward something”
  1. Foramen → foramina
    Origin: Latin, forare (to bore)
    An anatomical hole or opening
  1. Fossa → fossae
    Origin: Latin, fodere (to dig)
    An anatomical ditch, with only one open end
  1. Octopus → octopodes
    Origin: Greek, octo– (eight) + podos (foot)
    The animal with eight feet

Can you think of the plurals for these words? Leave a comment below!

  1. Plexus
  2. Isthmus
  3. Duodenum
  4. Platypus
  5. Rhinoceros (!)

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There are a number of ways of diagnosing disease: tissue biopsy, symptom matching, and of course, clinical signs. People often use the latter two terms interchangeably, especially since they are often paired together via the phrase “signs and symptoms.” But rigorously, these two words refer to two different things. Perhaps their etymologies will help differentiate them:

Sign
Origin: Latin, signum (sign/image)
Something the clinician notes in during a clinical encounter

Symptom
Origin: Greek, sym- (together) + piptein (to fall)
Something a patient reports to the clinician; something that “falls together” with something else

In other words, symptoms are subjective experiences while signs are objective experiences. For example, if I tell my doctor I have a fever, that is considered a symptom, but if he or she were to measure my temperature and find it elevated, it would be a sign. Another good example: pain is a symptom, since the perception of pain is unique to each patient. Tenderness, however, is a sign, since it is elicited by a clinician, e.g., applying pressure to the abdomen and eliciting an “ouch!”

stigmata rev

St. Francis Receives the Stigmata, by Antoni Viladomat (1678-1755)

There is another pair of terms that are often used together that is also often conflated. These words are stigma (plural stigmata) and sequela (plural sequelae). A stigma is a readily-visible (cutaneous or otherwise) or discernable sign that is characteristic of some disease. A classic stigma of liver disease is jaundice.A sequela, on the other hand, is an abnormal state or complication that results from a previous disease. A classic sequela of diabetes is diabetic nephrophaty. The etymologies of these words are relatively straight-forward:

Stigma
Origin: Greek, stizein (to mark/tattoo)

Sequela
Origin: Latin, sequi (I follow)

Interestingly enough, the word “stigmata” is also used in theology to refer to the bodily marks or sensations of pain associated with the crucifixion [Origin: Latin, crux (cross) + figere (to fix/bind)] of Jesus. Those who bear these stigmata are called “stigmatics” or “stigmatists,” and a common motif in classical painting is St. Francis of Assisi’s reception of the stigmata (see above). St. Francis supposedly received the stigmata of Christ for his great piety during the Feast of the Exaltation of the Cross after a forty-day fast.

Regarding jaundice, a stigma of liver disease, we know it to be the yellowing of the skin due to increased levels of bilirubin. Jaundice can, of course, be caused by a number of other conditions, e.g., deficiencies in certain enzymes (cf. Gilbert syndrome). There is one part of the body that is not said to be jaundiced when yellow; that honour falls on the eyes. When the eyes turn yellow due to, say, liver disease, we call it scleral icterus.

icterus rev

Jaundice
Origin: Latin, galbinus (yellow/yellow-green)

Icterus
Origin: Greek, ikteros
A bird said to cure jaundice when spotted

Hence we call it scleral icterus because it is with our eyes that we see the ikteros and become cured of our jaundice!

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Enzymes are biological catalysts that allow a host of chemical reactions to take place in organisms. They can also be used in synthetic chemistry to perform difficult reactions, e.g., forming carbon-carbon bonds. Enzymes (and more generally, all catalysts) do this by lowering the activation energy of a reaction and stabilizing the transition state. Where does the word enzyme come from?

Enzyme
 Origin: Greek, en– (in) + zyme (leavened)
Something leavened in

Louis Pasteur (Pasteur pipettes, pasteurization, etc.), a titanic French chemist of the 1800s, was studying the fermentation of alcohol by yeast.  He postulated that the agent responsible for fermentation was a “vital force,” and that only living organisms could perform the task. Wilhelm Kühne coined the term “enzyme” to refer to the process, but it was Eduard Büchner (Büchner funnel) who showed that cell-free yeast extracts could still ferment sugar into alcohol. For this, Büchner received the 1907 Nobel Prize in Chemistry. He named the agent responsible zymase.

pasteur and buchner

Left: Pasteur; Center: Kühne; Right: Büchner

Zymase
Origin: Greek, zyme (leavened) + –ase (enzyme suffix)
That which cleaves “leavened,” i.e., the substrate is from the yeast

Following Büchner’s convention, we use the suffix –ase to denote the substrate of an enzyme, e.g., an enzyme that catalyzes a reaction involving a peroxide is called a peroxidase. Note that this convention is not used for all enzymes. Here are some enzymes with interesting etymologies that are important for digestion:

Amylase
Origin: Greek, a– (without) + myle (mill) + –ase
That which cleaves something unmilled, i.e., starch

Pepsin
Origin: Greek, peptein (to digest)
That which cleaves proteins into peptides

Lipase
Origin: Greek, lipos (fat) + –ase
That which cleaves fats, e.g., triglycerides

Some enzymes require organic or inorganic cofactors in order to function. The organic cofactors can either be prosthetic groups, which are covalently bound to the enzyme, or they can be coenzymes, which are cleaved from the active site during the reaction. Some cofactors may be involved in allosteric modulation; here, an ion or molecule binds to an area away from the enzyme’s active site to modulate its activity.

biotin cofactor

Biotin (left) is a cofactor of pyruvate carboxylase (right)

Allosteric
Origin: Greek, allos (other) + stereos (solid, taken to mean 3D shape/position)
Pertaining to another space/position

Are there any cool enzymes with puzzling etymologies that you can think of? Leave a comment below and let’s explore!

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Here is a clinical scenario: a patient comes to your office for a routine examination. While examining the skin, you notice an ill-defined and oddly-colored brown spot on the patient’s back. Or perhaps while palpating the thyroid gland, you palpate something that doesn’t feel quite right. What is the next step in this patient’s care? If you thought to perform a biopsy, you’d be correct. Indeed, to derive insights from what a patient is suffering from, clinicians obtain a sample of tissue via biopsy from the suspect organ for the tissue to be studied histologically.

Biopsy
Origin: Greek, bios (life) + opsia (a sight)
A sight of life

Histology
Origin: Greek, histos (web/tissue) + logos
The study of tissue

This tissue can initially be examined grossly [L., grossus (thick/coarse)], i.e., by the naked eye, but clinicians often require insights from a pathologist to more completely characterize and understand the tissue they obtained. What does a pathologist study? Let’s take a look:

Pathology
Origin: Greek, pathos (suffering) + logos (word, taken to mean “study of”)
The study of suffering

This is a very generalized definition of pathology (which is absolutely wonderful to me), but let me offer my own comprehensive/digestible definition of pathology. Pathology is the molecular, histological, and gross study of disease processes and their clinical manifestations. Thus, staying true to its etymology, pathology is the systematic and scientific study of suffering. There are four main areas that pathologists explore to better understand disease: aetiology, pathogenesis, morphological changes, and clinical manifestations.

spitz papillary

Left: Spitz nevus (mole). Right: papillary thryoid carcinoma

Aetiology
Origin: Greek, aitos (cause) + logos
The study of the cause of a disease

Pathogenesis
Origin: Greek, pathos + genesis (origin/source)
The origin and development of disease

If all goes well, the pathologist will generate a diagnosis and a prognosis regarding the patient’s condition, and the clinician or the surgeon will proceed accordingly.

Diagnosis
Origin: Greek, dia– (through) + gignoskein (to know) + –osis (condition of)
A condition of knowing through, i.e., a distinguishing

Prognosis
Origin: Greek, pro- (for/before) + gignoskein + –osis
A condition of foreknowledge, i.e., the likely outcome

What tools does a pathologist use to actually study the tissue in question and generate a diagnosis? You’ll have to stay tuned to find out!

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I often find myself taking many modern medical advancements for granted. For instance, I can take over-the-counter medication to treat a cold or receive a vaccine to prevent the flu. We have countless specialists and medical professionals that can treat a whole host of illnesses and billions of dollars are poured into medical research each year. Truly, many of these medical achievements are miraculous, if one stops to think about them.

But consider: there was a time when the primary treatment for many diseases was a miracle. This is perhaps no where more evident than in medieval Europe, where a myriad number of saints could be invoked and relied upon to cure illness. The decline of the pagan religions of Greece and Rome was paralleled by the rise of Christianity in most of Western Europe. The god Asclepius, who was purported to cure those who slept at his temples, declined in popularity and gave rise to a pantheon of Christian saints with their own formidable healing powers. This is not to say that physicians did not exist in medieval times, but they were mostly reserved for the rich, leaving the vast majority of people reliant upon these holy persons. Let’s look at a few of these figures and examine their role in medieval and modern medicine.

Saint Anthony (251-356 AD) was an Egyptian Christian monk known for his asceticism and extreme piety. He is perhaps most remembered for his temptation in the desert, the subject of many paintings which depict this gruesome scene. In the middle ages, this saint was invoked when one was afflicted with either erysipelas [Gk. erythros (red) + pellas (skin)], a skin infection producing a bright red rash, or ergotism [Fr. argot (spur)], poisoning by the ingestion of a fungus that afflicts grains. Both conditions are known as “Saint Anthony’s Fire.” How did our friend Anthony come to be associated with these diseases? His remains were discovered and credited with the miraculous recovery of a French nobleman’s son from ergotism. In gratitude, he founded The Order of Saint Anthony in 1095 (an order which still exists today), and their monastery became famed for treating erysipelas and ergotism. It is interesting to note that ergot poisoning has been suggested as an explanation for “bewitchment” as it produces spasms, skin tingling, headaches,  and even psychosis.

temptation revThe Temptation of Saint Anthony, by Grünewald

Another Saint to have a disease named after him is Saint Vitus (died 303 AD). Vitus was a Sicilian Christian monk, known as the patron saint of dancers, actors, and comedians. This came about from the manic dancing that would take place in front of his statue during his feast day in the middle ages in order to venerate the saint. (This evokes images of the Maenads and their frenzied dancing for the god Bacchus.) With this in mind, which affliction(s) do you think Vitus was associated with? If you said epilepsy, you’d be correct. However, his name is attached to another disorder: Sydenham’s chorea [Gk. choreia (a dance)], otherwise known as St. Vitus’s Dance. This is a sign of acute rheumatic fever, a childhood infection caused by Group A streptococci. Thomas Sydenham (1624-1689), the “English Hippocrates,” first characterized the disorder. You can imagine what symptoms are produced by Sydenham’s chorea from its name alone: jerking and uncontrollable spasms of the face, hands, and feet, as if the patient were dancing manically. It is no wonder that the saint venerated by frenzied dancing should come to be associated with Sydenham’s chorea centuries before Sydenham made his observations. 

strep pyo and vitus

Left: S. pyogenes, the causative agent of acute rheumatic fever; right: the man himself, Saint Vitus

Let’s end with a look at the brother saints, Cosmas and Damian (died 287 AD). The brothers were born in Cilicia (Asia Minor) and their chief miracle is truly fascinating: they hold the distinction of successfully completing the first transplant surgery. The story goes that they amputated the gangrenous leg of a patient, which in those times was the best one could hope for. However, being imbued with divine power, the brothers were said to have taken the leg from a dead Moor (in some versions of the story, an Ethiopian) and miraculously transplanted it to the amputee. This predates the first modern organ transplants by centuries, and it is quite a tall tale. The fact remains that human beings were considering organ transplants long before they were feasible. What did the brothers get in return for their miraculous healing powers? Unfortunately, they lived during a time of great persecution against Christians by the Roman emperor Diocletian, and were thus incarcerated, pelted with stones, burned at the stake, shot full of arrows, sawn in half, and decapitated. But their legacy lived on, and the brothers became the patron saints of medicine during the middle ages. Christiaan Barnard, eat your heart out!

cosmos and damian

Left: Saints Cosmas and Damian at work with angelic assistants; right: how the pair met its end

You may be asking yourself, how were these saints invoked? How exactly did the masses interact with these larger-than-life figures? Many were venerated in monasteries and churches and could be prayed to in times of need. Priests and monks could give advisement on how and when to pray, and in many cases, acted like middlemen between the holy and the sick. Perhaps the most common way to interact with a saint was through relics. The importance of these objects cannot be understated. Relics could be articles of clothing, pieces of wood purported to be from the cross, and even body parts such as bones and blood. These objects were housed in healing shrines and places of worship—being in their mere presence could ensure health and recovery.

These are but a few of the many, many saints associated with their own diseases, each fascinating in their own right. Hopefully I’ve shed a bit of light on the medical practices and beliefs of our medieval forebears!

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At some point in our lives, we inevitably fall into some form of ill health. This usually necessitates a visit to a local physician or the hospital, and it may sometimes necessitate a visit from emergency medical services. Thus, it is not unreasonable to assume that most of us have seen the symbol of medicine in one of these settings as a logo of sorts. Except there is a slight problem: there are two snakes on that staff. That staff is, in fact, not the symbol of medicine. It is instead the caduceus, the staff of Hermes. The caduceus was the symbol of commerce, for Hermes is the god of commerce (and thieves…). The U.S. military adopted the caduceus as its symbol of medicine in the 1850s, and it erroneously stuck. The real symbol of medicine is the rod of Ascelpius (Gk. Asklepios).

rod vs caduceusAsclepius was a son of Apollo, and Asclepius took on Apollo’s role as the god of healing in the Greco-Roman pantheon. The etymology behind his name is contested, so I unfortunately have no insights on that matter. There are multiple versions of the story regarding how Asclepius acquired his legendary abilities, and one of the more common ones is this: Asclepius was once asked to cure a man named Glaucus. While doing so, a snake slithered up his staff, and Asclepius promptly killed it. Another snake slithered by with an herb in its mouth and Asclepius placed the herb in the dead snake’s mouth. Sure enough, the dead snake returned to life! Regardless of his “origin story,” long story short, he learned how to raise the dead. Using a snake as a symbol of healing is somewhat paradoxical, since in those days, a snake bite was a death sentence. But Asclepius, utilizing his newfound knowledge, could cure even snake bites—and was thus eventually deified as the god of medicine.

asclepius vs zeus

Asclepius (left) and Zeus (right) share many facial features in classical sculptures

Asclepius was so skilled in medicine that he was asked by Artemis to revive Hippolytus, the son of Theseus and Hippolyta. He was able to do so successfully, and when Hades got word of this, he complained to Zeus that Asclepius was robbing him of his souls. Zeus struck Asclepius down with a thunderbolt to end this traveshamockery (travesty + sham + mockery). Apollo was so enraged that he killed the Cyclopes (singular: Cyclops), who fashioned Zeus’s thunderbolts. Outraged in turn, Zeus forced Apollo to be a servant to King Admetus of Thessay for one year. When Apollo returned to Olympus, Zeus revived the Cyclopes and resurrected Asclepius, turning him into a god.

Outside of the myth, why a snake coiled around a stick? One theory is that the symbol represents the painful process of treating dracunculiasis, better known as Guinea worm disease.

Dracunculiasis
Origin: Neo-Latin, draco (dragon) + -cule (diminutive) + -iasis (condition of)
Condition of small dragons/serpents

Perhaps a picture would illustrate why this makes sense:

guinea worms rev

As a side note, former president Jimmy Carter has been monumental in the global effort to eradicate the Guinea worm, for dracunculiasis is a truly wretched condition. He was recently interviewed and said “I would like the last Guinea worm to die before I do.” (Jimmy Carter was recently diagnosed with melanoma with metastases to the brain and liver.)

Back to our story: many temples were built throughout Greece dedicated to Asclepius. Those who were sick would come and spend a night at the Asclepion, and Asclepius would visit the patient in his or her dreams and relay to them the cure to their disease. One other interesting tidbit is that there were hordes of nonvenomous snakes, colloquially called Aesculapian snakes (Zamenis longissima), that would slither around the temples to promote healing!

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Meningitis (plural meningitides) is a nasty condition. From the first post, we already know that meningitis is defined as the inflammation of the meninges. The meninges (singular meninx) are the protective coverings of the brain, and there are three layers, listed outermost to innermost:

  1. Dura mater (Latin, “hard mother,” since it is the thickest layer)
  2. Arachnoid mater (Neo-Latin, “spider-like mother,” since it resembles a spider web)
  3. Pia mater (Latin, “pious mother,” erroneous translation from Arabic umm raqiqah for “tender mother”)

The dura mater is also known as the pachymeninx and the arachnoid mater + pia mater are also known as the leptomeninges.

meninges

Pachymeninx
Origin: Greek, pachy (thick) + meninx (membrane)
Thick membrane, i.e., the dura mater

Leptomeninges
Origin: Greek, leptos (thin) + meninges (membranes)
The thin membranes, i.e., the arachnoid mater and the pia mater

Meningitis can be caused by bacteria, viruses, autoimmune phenomena, or trauma. If the inflammation is caused by bacteria, it is said to be (quite logically) a bacterial meningitis, but if it is caused by the latter three, it is said to be an aseptic meningitis.

Aseptic
Origin: Greek, a- (without) + sepein (to cause decay)

Though the other aetiologies “cause decay,” septic is reserved for bacteria in the medical lexicon. It is important to note that the aseptic meningitides, though wretched, do not typically cause mortality. The bacterial meningitides, however, must be identified and treated swiftly, for they have a relatively high mortality. It is for this reason that if a case of bacterial meningitis is suspected, antibiotics are indicated for immediate use, whether or not the patient truly has a bacterial meningitis. Neutrophils in the cerebrospinal fluid (CSF) is a classic diagnostic marker of bacterial meningitis:

csf pleo rev

There are numerous signs that can hint towards a patient suffering from meningitis, but two of the classic ones are nuchal rigidity (neck stiffness) and photophobia.

Nuchal
Origin: Arabic, nukah (spine)
Used in English as an adjective for the neck

Photophobia
Origin: Greek, photos (light) + phobos (fear) + -ia (condition of)
Condition of the fear of light

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When you think “vessel” and “neck,” what words come to mind? For me, the first two words I think of are carotid and jugular. I’ve heard these words used in the vernacular every so often, especially the latter. If someone wants to convey a sentiment of “going for the kill” or delivering a coup de grace, that person can say he or she is “going for the jugular.” Let’s start with this one:

Jugular
Origin: Latin, jugulum (throat)
Named for the fact the jugular veins are near the throat

jugular

There are two jugular veins, one external and one internal on each side of the body. The internal jugular is covered by the sternocleidomastodeus muscle, while the external one is readily visible. These two veins are extremely important because they drain the deoxygenated blood from the head back to the superior vena cava.

What about the other vessel(s) of interest? There is a common carotid artery on both sides of the body, and this artery branches into the internal and external carotid arteries. The former supplies blood to the brain, while the latter supplies blood to the face and head. The etymology is rather interesting:

Carotid
Origin: Greek, karos (stupor)
So called from Galen’s observation that their compression causes stupor/somnolence

carotid rev

If one were to bilaterally massage both carotid sinuses (the point at which the common carotid bifurcates), the baroreceptors of the sinus are fooled into thinking there is a higher-than-normal blood pressure. To compensate, the blood pressure decreases, resulting in a sensation of stupor. Interestingly enough, there is a therapeutic use for this maneuver: the alleviation of supraventricular tachycardia:

Supraventricular tachycardia
Origin: Latin, supra– (above) + ventricle (chamber of the heart; translates to belly, for the ventricles comprise the “belly” of the heart)
Origin: Greek, tachys (swift) + kardia (heart)
A fast pulse due to improper electrical activity above the level of the ventricles

What other afflictions could these vessels suffer from? One thing that can go wrong with the carotid artery is carotid artery stenosis:

Stenosis
Origin: Greek, stenos (narrow/close) + -osis
Condition of narrowness, taken to mean a narrowing

Carotid artery stenosis is oftentimes caused by atherosclerosis, or the reduction of the interior arterial (luminal) diameter due to the accumulation of gunk. This gunk is a lovely mixture of dead cells, cholesterol, and fats.

Atherosclerosis
Origin: Greek, athres (gruel) + sklerein (to harden) + –osis
Condition of the hardening of gruel

Sounds delicious!