Definition of decapods:
(n) :
A decapod, the 0-10-0 (UK) and 2-10-0 steam locomotive configurations.
(n) :
(zoology) Any crustacean, of the order Decapoda, such as crabs or lobsters.
(adj) :
(zoology) Having ten legs.
(n) :
(zoology) Any of various animals having ten legs or similar appendages, especially mollusks such as squid and cuttlefish.
(n) :
(rail transport) A nickname for either the 0-10-0 or 2-10-0 train configurations. Sometimes capitalized.