Alteration (by folk-etymology, influenced by fish) of Middle English crevis, from Old French crevice ("crayfish"; > Modern French: écrevisse), from Old Frankish *krebitja (“crayfish”), diminutive of Old Frankish *krebit (“crab”), from Proto-Germanic *krabitaz (“crab, cancer”), from Proto-Indo-European *grebʰ-, *gerebʰ- (“to scratch, crawl”). Akin to Old High German krebiz ("edible crustacean, crab"; > Modern German Krebs (“crab”)), Middle Low German krēvet (“crab”), Dutch kreeft (“crayfish, lobster”), Old English crabba (“crab”). More at crab.
crayfish (plural crayfishes or crayfish)
- (New England, Michigan, Wisconsin, Minnesota) A freshwater crustacean (Cambaridae) resembling a small lobster, sometimes used as an inexpensive seafood or as fish bait.
- (Australia, New Zealand, South Africa) A rock lobster.
The term crayfish predominates in New England (including New York and Pennsylvania) and in Michigan, Wisconsin and Minnesota. In most of the United States—in the South, especially in Louisiana and Texas; in the Midwest and in the West—crawfish predominates. In a belt stretching across Kentucky through Missouri, Arkansas, Kansas, and Oklahoma, and in Oregon and northern California, the term crawdad predominates.