An octopus (pl.: octopuses or octopodes[ a ]) is a soft-bodied, eight-limbed mollusc of the order Octopoda (/ ɒkˈtɒpədə /, ok-TOP-ə-də[ 3 ]). The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids.