A crustacean is a member of a class of arthropods that live in water. Some of your favorite seafood comes from crustaceans — crabs, lobsters, and shrimp.

There are plenty of fish in the sea, and there are also plenty of crustaceans: strange-looking aquatic critters who usually have at least four pairs of limbs, plus a segmented body and a chitinous exoskeleton. If you think of a crust as being a little like a shell, that can help you remember crustaceans are essentially critters that have shells. Our word crust is from Latin crusta (shell or crust).

Definitions of crustacean
  1. noun
    any mainly aquatic arthropod usually having a segmented body and chitinous exoskeleton
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    malacostracan crustacean
    a major subclass of crustaceans
    decapod, decapod crustacean
    crustaceans characteristically having five pairs of locomotor appendages each joined to a segment of the thorax
    typical crabs
    stomatopod, stomatopod crustacean
    a kind of crustacean
    branchiopod, branchiopod crustacean, branchiopodan
    aquatic crustaceans typically having a carapace and many pairs of leaflike appendages used for swimming as well as respiration and feeding
    copepod, copepod crustacean
    minute marine or freshwater crustaceans usually having six pairs of limbs on the thorax; some abundant in plankton and others parasitic on fish
    mussel shrimp, ostracod, seed shrimp
    tiny marine and freshwater crustaceans with a shrimp-like body enclosed in a bivalve shell
    barnacle, cirriped, cirripede
    marine crustaceans with feathery food-catching appendages; free-swimming as larvae; as adults form a hard shell and live attached to submerged surfaces
    decapod having eyes on short stalks and a broad flattened carapace with a small abdomen folded under the thorax and pincers
    any of several edible marine crustaceans of the families Homaridae and Nephropsidae and Palinuridae
    crawdad, crawdaddy, crawfish, crayfish
    small freshwater decapod crustacean that resembles a lobster
    hermit crab
    small soft-bodied marine crustaceans living in cast-off shells of gastropods
    small slender-bodied chiefly marine decapod crustaceans with a long tail and single pair of pincers; many species are edible
    shrimp-like decapod crustacean having two pairs of pincers; most are edible
    tropical prawn
    edible tropical and warm-water prawn
    shrimp-like planktonic crustaceans; major source of food for e.g. baleen whales
    opossum shrimp
    shrimp-like crustaceans whose females carry eggs and young in a pouch between the legs
    mantis crab, mantis shrimp
    tropical marine burrowing crustaceans with large grasping appendages
    any of various small terrestrial or aquatic crustaceans with seven pairs of legs adapted for crawling
    a kind of malacostracan crustacean
    daphnia, water flea
    minute freshwater crustacean having a round body enclosed in a transparent shell; moves about like a flea by means of hairy branched antennae
    fairy shrimp
    small freshwater branchiopod having a transparent body with many appendages; swims on its back
    Artemia salina, brine shrimp
    common to saline lakes
    tadpole shrimp
    a kind of branchiopod crustacean
    brit, britt
    minute crustaceans forming food for right whales
    cyclops, water flea
    minute free-swimming freshwater copepod having a large median eye and pear-shaped body and long antennae used in swimming; important in some food chains and as intermediate hosts of parasitic worms that affect man e.g. Guinea worms
    fish louse
    a kind of copepod
    Balanus balanoides, acorn barnacle, rock barnacle
    barnacle that attaches to rocks especially in intertidal zones
    Lepas fascicularis, goose barnacle, gooseneck barnacle
    stalked barnacle that attaches to ship bottoms or floating timbers
    type of:
    invertebrate having jointed limbs and a segmented body with an exoskeleton made of chitin
  2. adjective
    of or belonging to the class Crustacea
    synonyms: crustaceous
DISCLAIMER: These example sentences appear in various news sources and books to reflect the usage of the word ‘crustacean'. Views expressed in the examples do not represent the opinion of or its editors. Send us feedback
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