Crustaceans from the suborder Reptantia, order Decapoda, subclass Cirripedia, class and subphylum Crustacae. They have a broad, flat body, a tiny abdomen usually tucked under the cephalothorax, and five pairs of legs used for walking or swimming. They are abundant and distributed worldwide. They feed on a range of organisms from plankton to live prey or detritus. Crabs are scavengers and live in estuaries, bays, inlets and muddy shorelines. The females carrying the young around for several weeks after spawning. True crabs have up to 19 pairs of appendages. See also Crustacea.

Alternative form for crab : crabs.