mal·​a·​cos·​tra·​can ˌma-lə-ˈkä-stri-kən How to pronounce malacostracan (audio)
: 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
malacostracan adjective

Word History


ultimately from Greek malakostrakos soft-shelled, from malakos soft + ostrakon shell — more at mollify, oyster

First Known Use

1835, in the meaning defined above

Time Traveler
The first known use of malacostracan was in 1835

Dictionary Entries Near malacostracan

Cite this Entry

“Malacostracan.” Dictionary, Merriam-Webster, Accessed 18 Jul. 2024.

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