Definition of "crayfish"

Any of numerous freshwater decapod crustaceans in superfamily Astacoidea or Parastacoidea, resembling the related lobster but usually much smaller.

1. (New England, Michigan, Wisconsin, Minnesota) A freshwater crustacean (family Cambaridae), sometimes used as an inexpensive seafood or as fish bait.  examples

(Australia, New Zealand, South Africa) A rock lobster (family Palinuridae).  examples

(Australia) A freshwater crayfish (family Parastacidae), such as the gilgie, marron, or yabby.  examples

(Singapore) The species Thenus orientalis of the slipper lobster family (Scyllaridae).  examples

to catch crayfish  examples

Alternative form of crawfish (to backpedal, desert, or withdraw)  examples