malacostracan crustacean ma·la·cost·racancrustacean uncommon noun 1. a major subclass of crustaceans Synonymsmalacostracan crustacean Related words Broader terms crustacean Narrower terms krillopossum shrimpisopodamphipod Parts Malacostraca WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
