What is the meaning of Decapod?

Having ten legs.

Any of various animals having ten legs or similar appendages, especially mollusks such as squid and cuttlefish.

Any crustacean, of the order Decapoda, such as crabs or lobsters.

A nickname for either the 0-10-0 or 2-10-0 train configurations. Sometimes capitalized.

decapod

Source: wiktionary.org