The Anatomy Word of the Day will return on January 2nd, 2008.

Happy holidays everyone!


From the archives:

Clavicle, the collarbone: the slender, sigmoid-shaped bone that links the manubrium of the sternum to the acromion of the scapula. From the Latin clavicula, ‘small key’, a translation of the Greek kleidion.

The word was coined in the 12 century by the translators of the 10 century Persian physician Abu Ali Sina (his name was often latinized as Avicenna) whose works were a mainstay of European medicine the until the mid-17th century. Ali Sina used alchiab, ("the key") for collarbone, this from his own translations of Latin anatomy treatises from ancient Rome.

Ala Sina's translators returned to the Latin, renaming alchiab the clavicula, the diminutive of clavis (key).

But why key? A common tale is that the Romans likened the collarbone to a clavis simply because of similarity in appearance. However, it was probably not Roman door keys, which do not resemble clavicles, that were alluded to but rather S-shaped lift-latches, a primitive type key type first seen the Iron Age and common in Rome.

A Roman lift-latch ca 350 BC:
designed to allow a door-latch

to be lifted through a hole in the door.
It acted as a simple key. England, ca 350 BC

It has also been suggested that the relationship of the clavicle to a key is metaphorical, given that the bone "locks" the shoulder girdle to the trunk. Of course neither of these explanations are mutually exclusive, as the key shape lends itself nicely to the metaphor.

Perhaps though, "key" was a mistranslation by Ali Sina: yet another explanation is that the name comes from the resemblance of the bone to a toy, a curved stick called a clavicula or clavis trochi used by Greek and Roman children to roll, or trundle, a hoop.

A clavicula or clavis trochi, a child's toy for trundling a wheel in ancient Greece and Rome; from the Dictionary of Greek and Roman Antiquities, 3rd Edition by Anthony Rich. 1874

A minority view holds that the term has nothing to do with keys or trundles or metaphors but rather is named for the clavicle's resemblance to the sinuous tendrils of some plants. The Latin word for tendril is also clavicula.

The original Greek kleidion lives on in sternocleidomastoid muscle

Anatomically unrelated: the clavichord was the first keyboard instrument.


From the archives:

Finger comes unaltered from Old English (i.e. Anglo-Saxon). Indeed, the word is found, spelling unchanged, in most of the Germanic languages (e.g. German, Swedish, and Danish); The Dutch get by with vinger.

Each of the fingers have had their own Latin names. Some examples are given in the Aberdeen Beastiary, published in Scotland in the 14th century. (A bestiary is a collection of descriptions of all sorts of animals - some real, some imaginary - and other features of the natural or unnatural world.) From the Bestiary:

  • "The [first] finger, index, is also known as salutaris or demonstratorius, the greeting or indicating finger, because we generally use it in greeting, showing or pointing."
  • "The [second, middle] finger is called impudicus, lewd; it is frequently used to express the pursuit of something shameful."
  • "The [third] is the ring finger, anularis, because it is the one on which a ring is worn. It is also called medicinalis, the medical finger, because it used by physicians to smear on ground-up salves."
  • "The [fourth] finger is called auricularis, because we scrape our ear, auris, with it."
The image “http://www2.jpl.nasa.gov/galileo/images/finger.gif” cannot be displayed, because it contains errors.
A digital display: Galileo Galilee's impudicus finger is on exhibit at the Museo di Storia della Scienza in Florence, Italy. www2.jpl.nasa.gov/galileo/finger.html


From the archives:

Malar - relating to the cheek. From the Latin mala, cheek. The only remaining use for the word in anatomy is seen in "malar lymph nodes". The "cheek bone" was once called the malar, but the Terminologia Anatomica now only recognizes zygomatic bone.

Mala is probably derived from malus, Latin for apple; see the photo below for some evidence as to why apples and cheeks have been linked.

Definitely derived from malus is malic acid, first isolated in apple juice in the 18th century and responsible for the tart taste of apples, grapes, and rhubarb, among other foods.


From the archives:

Fascicle comes from fasciculus, the diminutive of the Latin word for bundle, fascis. The term is used to describe either bundles of axons within nerves or bundles of muscle cells within muscles (fascicles form the visible grain of a muscle as well as the strings of pot roast that may get stuck between your teeth).

Six fascicles, each a bundle of axons, seen in a cross-section of a small nerve about 1 mm in diameter.
From Wikipedia.com

In ancient Rome, the fasces (plural of fascis) was the name given to the official insignia of authority: an axe suspended over a bound bundle of birch rods. Through the centuries, fasces became a symbol for solidarity as well (an allusion to the bundle), eventually giving rise to the Italian word for a "united political group", fascio. One such organization, founded in Italy in 1919 by a newspaper editor named Benito Mussolini, was the Fasci di Combattimento, a collection of disgruntled Italian citizens that used the fasces as its logo.

In 1921 Mussolini and his group, by then a full-blown political party, had gained total control of Italy, in part through brutal suppression of the opposition. In the same year the English press, in reference to Mussolin's Fasci organization, began calling members of the movement fascists and its ruthless philosophy fascism. The names stuck.
The image “http://upload.wikimedia.org/wikipedia/commons/a/a6/Fasces.png” cannot be displayed, because it contains errors.
A ancient Roman fasces in a bas-relief at the Matte Palace in Rome. From A Dictionary of Roman Antiquities, by Antony Rich, Appelton, 1874.

A fasces was on the US dime from 1916-1945.


Coccyx, the tail bone, comes from kokkyx, Greek for cuckoo. One of the oldest words in anatomy, it was coined around 300 B.C. by Herophilus who, it is said, was inspired by the cuckoo's bill (probably that of the common cuckoo, Cuculus canorus). However, he was more likely taken by the anterior portion of the cuccko skull, which bears a greater resemblance to the coccyx than just the bill alone (see the photos below).


A more fanciful explanation of the link between cuckoo and coccyx was provided in the early 17th century by the French anatomist and surgeon Johann Riolan, who inexplicably insisted that the sound of flatus emanating from the coccygeal region was reminiscent of the call of a cuckoo and thus was the inspiration for Herophilus. Never mind that neither the male nor the female of any cuckoo species has a call that you'd confuse with flatulence (indeed, the classic sound of the cuckoo clock was patterned after the call of the male common cuckoo). Perhaps the professeur simply had a talented friend.

Nonetheless, the coccyx has been called the "whistle bone" for its proximity to the source of digestive tract toots.

Unrelated but interesting: The word "cuckold" (a man whose wife has cheated on him) also comes from cuckoo, derived from the female's nasty habit of laying eggs in nests not her own and thus tricking other birds into raising her young. Likewise, a cuckold may raise children that aren't his.

Image credits
coccyx from
The common cuckoo from
cuckoo skull


From the archives:

Achilles tendon: the common tendon of the gastrocnemius, soleus, and sometimes the plantaris muscles; also known as the calcaneal tendon. It attaches to the posterior portion of the calcaneus or heel bone.

The name comes indirectly from Greek mythology: After receiving a prophecy that her young son, Achilles, would die in battle, the goddess Thetis dipped him into the magical, protective waters of the river Styx. However, she held him by his heel which was not immersed and thus remained vulnerable. Years later, as luck would have it, Achilles was fatally wounded during the Trojan War: a poison arrow in the back of the foot, a region henceforth known as Achilles heel (and so, metaphorically, an "Achilles heel" is a seemingly insignificant but in fact critical weakness).

It wasn't until 1693 that the term Achilles tendon appeared (chorda Achillis in the original Latin), so named by the resourceful Dutch anatomist Philip Verheyen while dissecting his own amputated leg.

Thetis dipping Achilles in the river Styx.
Sculpture by Thomas Banks (1735-1805)
Victoria and Albert Museum, London

Philip Verheyen dissecting his Achilles tendon. Artist: anonymous; from the collection of Pieter Deheijde, Amsterdam


From the archives...

Sphincter was first used by Galen in the 2nd century, probably as an allusion to the talented constrictor that was the Sphinx of Greek mythology. A chimera with the head of a woman and the body of a winged-lion, and who received her name from the Greek sphingo, "I strangle", the Sphinx sat outside Thebes and demanded that all passersby answer her riddle: "Which creature travels in the morning on four feet, at noon on two, and in the evening upon three?" She strangled anyone unable to answer. Oedipus finally provided the correct response.

A fourth century BC kylix
from the Vatican Museum showing
Oedipus with the Sphinx


Note that the Grecian Sphinx is not the same as the sphinxes of Egypt: The Greek name "sphinx" was inexplicably applied some 2600 years ago to an Egyptian chimeric lion, even though it is wingless and has the head of a man not a woman. The original Egyptian name of this creature is unknown. The most famous of the Egyptian sphinxes is the Great Sphinx of Giza.


Colostrum, the first milk secreted by the mother after giving birth, comes from the Latin colostra, a word with the same meaning used by the Romans. Colostra appeared in English in the late 16th century, joining the equivalent terms of "beestings" and "green milk" (both of which, unfortunately, having since disappeared from the language).

By the early 19th century, the spelling had changed to colostrum.

Aulus Plautius, the politician and general who lead the Roman conquest of Britain in 43 A.D., used colostra as a word of endearment: Meum mel, meum cor, mea colostra: "my honey, my heart, my colostra".


Cornea, from the Latin, cornu, animal horn, and corneus, horny (i.e., tough and hard like a horn).

It seems strange for the cornea, the transparent and seemingly delicate anterior surface of the eye, to be etymologically related to an animal horn but it was recognized long ago that the structure,
when dissected, is surprisingly hard; thus its "horny" nature.

The stratum corneum, the name given to tough outer layer of the skin, also comes from cornu, as does the corniculate cartilage of the larynx (literally, corniculate means "shaped like a little horn").

Some other words derived from cornu include Capricorn (literally, a goat's horn), cornucopia (the horn of plenty), and cornet (which, like all musical horns, can trace its ultimate ancestry back to the animal horns used as musical instruments by prehistoric humans).

Note that although the coronoid processes of the mandible and ulna have a shape reminiscent of animals horns, "coronoid" is derived
not from cornu but from korone, Latin for crow, or korax, Latin for raven. Charitably, these structures also resemble a corvid's beak, though the Greeks often used korax for many structures with a slightly hooked or pointed tip, such as the handles of their doors (see coracoid).


Foramen is taken directly from the Latin word for hole, foramen, which in turn comes from the Latin forare, to pierce.

There are 40 named foramina in the Terminologia Anatomica; most are in the skeletal system and the majority of those are in the skull.

Perforate is also derived from forare.