dec·a·pod 
(dĕkə-pŏd′)
(dĕkə-pŏd′)n.
1. Any of various crustaceans of the order Decapoda, characteristically having five pairs of walking legs attached to the thorax and three pairs of maxillipeds used for feeding, and including the crabs, lobsters, and shrimps.
2. Any of various cephalopod mollusks having eight arms and two tentacles, and including the squids and cuttlefishes.
[From New Latin Decapoda, crustacean order name : DECA- + -poda, -pod. Sense 2, from New Latin Decapoda, former cephalopod order name : DECA- + -poda, -pod.]
de·capo·dan (dĭ-kăpə-dən), de·capo·dous (-dəs) adj.