Which came first: leech the doctor or leech the worm?

Comparative philology is a great combination of linguistics and history, so let’s do a little bit. We might wonder why leech used to be a word for the doctor and at the same time for the worm used by the doctor. Obviously, this begs the question of which came first: leech the doctor or leech the worm?
 

Dr. Lewis Thomas knew how to go about answering questions the right way: “The evolution of language can be compared to the biological evolution of species, depending on how far you are willing to stretch analogies. The first and deepest question is open and unanswerable in both cases: how did life start up at its very beginning? What was the very first human speech like?”

He was really THE man, Thomas was.

Anyhow, let’s get back to language and species. Since fossils exist for both, we can trace back to near the beginning. Prokaryotes were the earliest forms of life and they left prints in rocks dating back to 3.5 billion years…actually, on second thought, let’s skip some of the biology.

Of course, language fossils are more recent, but they can also be scrutinized and theororized (fine, I know it’s theorized). Words are fascinating and they can most likely be rooted back about 20,000 years to Indo-European ancestors of Sanskrit, Greek, Latin, and Germanic tongues, among others. Take our example of the two types of leeches and you see why it’s not all clear on the surface. Leech the doctor goes back to the word “leg,” meaning “to collect” and with derivatives meaning “to speak.” Implications of knowledge started to follow the word, as it became “laece” in Old English, “lake” in Middle Dutch, and “lekjaz” in early German. Leech the worm is classified by the Oxford English Dictionary as being “lyce” in the tenth century, then “laece” a bit later, and “leech” in the Middle Ages. At some point, leech the doctor and leech the worm (and, incidentally, leech the tax collector) fused into the same general idea of collecting (blood, fees, etc.).

Other medically related words also have interesting stories. “Doctor” comes from “dek,” meaning proper, acceptable and useful. In Latin, this became “docere” – to teach – and “discere” – to learn and disciple.

The word “medicine” came about from the root “med,” used to refer to measuring things out. In Latin, “mederi” meant “look after and heal.” The same root gave rise to words such as “moderate” and “modest,” perhaps good words for current students and doctors to reflect on.

Admittedly, most discussions of medical etymology aren’t this mature. We learn about “cardiac tamponade” (where fluid accumulates in the sac surrounding the heart) and then realize that “tampon” is French for “plug.” We see images of the “tunica intima” (which lines arteries and veins) and whisper about how it’s like an intimate tunic. I could talk about words all day, every day. For now, over and out!