Other forms: crustaceans
A crustacean is a hard-shelled water animal with jointed legs. Crabs and other crustaceans, a crustacean shell, crustacean allergy.
Crabs, lobsters, prawns, shrimp and barnacles are all in the group, and so is the woodlouse, which is a crustacean living on land. They grow by moulting the whole shell and are soft and defenceless for a day or two afterwards.
1nouncrustaceanA hard-shelled water animal with jointed legs.
“The rock pool was full of tiny crustaceans scuttling under the seaweed.”
crustacean is an animal group.
From Latin crusta, a hard shell or crust. Crust and crystal are relatives.
From Crustacea + an.
Etymology from Wiktionary, CC BY-SA