Definition of malacostracan
: any of a large subclass (Malacostraca) of crustaceans having a thorax consisting of eight segments usually covered by a carapace and including the decapods and isopods
Learn More about malacostracan
Britannica.com: Encyclopedia article about malacostracan
Seen and Heard
What made you want to look up malacostracan? Please tell us where you read or heard it (including the quote, if possible).