plural noun
Mal·​a·​cos·​tra·​ca | \ ˌmaləˈkästrəkə \

Definition of Malacostraca

: 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)

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Other Words from Malacostraca

malacostracan \ ¦⸗⸗¦kästrəkən How to pronounce Malacostraca (audio) \ adjective or noun
malacostracous \ -​kəs \ adjective

First Known Use of Malacostraca

1819, in the meaning defined above

History and Etymology for Malacostraca

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

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The first known use of Malacostraca was in 1819

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Cite this Entry

“Malacostraca.” Dictionary, Merriam-Webster, Accessed 20 Jan. 2021.

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