ἰχθύς

ἰχθύς (ichthys, "ikh-THÜSS") is the Greek word for fish, and the record shows it as an object of curiosity and appetite more than reverence: 147 occurrences across 48 works. It swims hardest through Herodotus's Histories — "Inquiries" (29), the fish of the Nile and of strange rivers — and Aristotle's De Respiratione, "On Breathing" (18), where the standing question is how a fish breathes at all. The Iliad (9), the book of Tobias (9), and the Odyssey (8) follow, with Diogenes Laertius's Lives of Eminent Philosophers (6) trailing after. The word lives, in this corpus, at the meeting of the market stall and the natural-science problem.

LSJ (Liddell–Scott–Jones, 1940) records the plain animal and then two human extensions the Greeks made from it: the fish-market — "to the fish," meaning to the market stalls — and "a stupid fellow," the fish as an image of a cold, gaping, dumb thing. Beekes (Etymological Dictionary of Greek, Brill 2010) glosses it simply "fish."

On the deeper history the record does carry a pointer, and it is an honest one. In the view of Beekes (2010) and Chantraine (Dictionnaire étymologique de la langue grecque, 1968–80), ἰχθύς has cognates in Baltic — the Lithuanian fish-word — and in Armenian, but no clean, agreed reconstruction stands behind it. It is one of those inherited words whose ancestry the dictionaries can gesture toward without quite closing.

Of the many attestations, the record fixes one surface for us to hold: the genitive plural ἰχθύων ("ikh-THÜ-ōn," "of fishes") in Xenophon's Anabasis, "The March Up-Country" (1.4.9) — a river, in a soldier's account, simply full of fish. Food, wonder, insult, and a puzzle of breathing: the culture kept turning the plain creature over.

If the same word is dinner, an idiot, and the hardest kind of animal to explain, what did the Greeks not quite know about the fish?