The name "crayfish" comes from the Old French word escrevisse (Modern French écrevisse).[2] The word has been modified to "crayfish" by association with "fish" (folk etymology).[2] The largely American variant "crawfish" is similarly derived.[2]
Some kinds of crayfish are known locally as lobsters, crawdads,[3] mudbugs,[3] and yabbies. In the Eastern United States, "crayfish" is more common in the north, while "crawdad" is heard more in central and southwestern regions, and "crawfish" further south, although there are considerable overlaps.[4]
The study of crayfish is called astacology.[
Other animals[edit]
In Australia, New Zealand and South Africa, the term crayfish or cray generally refers to a saltwater spiny lobster, of the genus Jasus that is indigenous to much of southern Oceania,[6] while the freshwater species are usually called yabby or kōura, from the indigenous Australian and Māori names for the animal respectively, or by other names specific to each species. Two exceptions are the freshwater Tasmanian giant freshwater crayfish; and the Murray crayfish, which belongs to the family Parastacidae and is found on Australia's Murray River.
In Singapore, the term crayfish typically refers to Thenus orientalis, a seawater crustacean from the slipper lobster family.[7][8][9] True crayfish are not native to