- crayfish, crawfish, crawdad, ecrevisse - tiny lobster-like crustaceans usually boiled briefly
--1 is a kind of shellfish
--1 is a part of American crayfish; Old World crayfish, ecrevisse - crayfish, crawfish, crawdad, crawdaddy - small freshwater decapod crustacean that resembles a lobster
--2 is a kind of decapod crustacean, decapod
--2 is a member of Astacidae, family Astacidae, Astacura
--2 has particulars: Old World crayfish, ecrevisse; American crayfish