In a Word: A Crayfish Is Not a Fish

Senior managing editor and logophile Andy Hollandbeck reveals the sometimes surprising roots of common English words and phrases. Remember: Etymology tells us where a word comes from, but not what it means today.

If you’ve ever laid eyes on a crayfish, the title of this article may seem self-evident. It’s plain to see that, with its pincers and shell, a crayfish is some sort of crustacean, maybe an oversized insect. Crayfish look like tiny lobsters — in fact, in some areas, the spiny lobster or langoustine is also referred to as a crayfish.

But as this is a column about etymology, when I say that a crayfish isn’t a fish, what I mean is that the word isn’t a compounding of cray and fish. (What is a cray anyway?)

The resemblance of crayfish to marine crustaceans wasn’t lost on the people of old. In Old French, this little beastie was called crevice or escrevice (it’s écrevisse in Modern French). Unlike the majority of French words, this doesn’t derive from Latin. It’s believed to come from either a Frankish or Germanic word that is a diminutive of the word for “crab.” (For instance, Old High German for “crab” is krebiz.)

So, back in the 1200s, people were essentially referring to crayfish as “little crabs.”

The word crossed the English Channel by the 14th century as the Anglo-French word variously spelled as creveis, crevis, and escreveice. If you say those words aloud a few times, you should be able to guess at how we arrived at the modern version: Influenced by fish — more common as both a word and a creature — the final syllable of creveis evolved into -fish through the processes of folk etymology.

The cray- part was just a more natural English spelling of the French pronunciation. Accents being what they are, though, not everyone pronounced creveis or its descendants the same: Though crayfish is the standard form, this small crawler is also known as a crawfish. This version is likely also influenced by the false belief that the name is a simple compound word. The second half, fish, is fine, but cray isn’t a word; craw is. It’s another word for “stomach.” And since people not only put these crustaceans into their own stomachs but also use them as bait for fish, crawfish simply makes more sense as a compound word, doesn’t it?

This sense of the word as a compound might also explain when, especially west of the Appalachian Mountains — including where I grew up in the Midwest — they’re also called crawdads and crawdaddies. Exactly how this connected to a father figure I’m not sure I want to know.