/ Dictionary / Index M malacostracan: Meaning and Definition of Find definitions for: mal•a•cos•tra•can Pronunciation: (mal"u-kos'tru-kun), [key] — adj. belonging or pertaining to the crustacean subclass Malacostraca, which includes the lobsters, shrimps, crabs, etc. —n. a malacostracan crustacean. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. malacopterygian maladaptation Related Content Daily Word Quiz: feline Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language