- 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 - Old World crayfish, ecrevisse - small crayfish of Europe and Asia and western North America
--2 is a kind of crayfish, crawfish, crawdad, crawdaddy
--2 is a member of Astacus, genus Astacus
--2 has parts: crayfish, crawfish, crawdad, ecrevisse