plural noun

: a major subclass of Crustacea including most of the well-known marine, freshwater, and terrestrial members of the group (as lobsters, crabs, shrimps, sow bugs, beach fleas)
malacostracan adjective or noun

Word History


New Latin, from Greek malakostraka, neuter plural of malakostrakos soft-shelled, from malak- malac- + -ostrakos (from ostrakon shell)

First Known Use

1819, in the meaning defined above

Time Traveler
The first known use of Malacostraca was in 1819

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Dictionary Entries Near Malacostraca

Cite this Entry

“Malacostraca.” Dictionary, Merriam-Webster, Accessed 19 Jul. 2024.

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