Ichthyological terms, not general ones.
Any member of the crustacean order Decapoda, comprising species possessing 5 pairs of jointed, thorassic limbs such as crabs, crayfish, lobsters and shrimp. Also used historically in reference to molluscs of the Cephalopod superorder Decapodiformes, members of which have 8 short limbs plus 2 longer tentacles and include cuttlefish and squid.
A decapod gill associated with the articular membrane between the coxa of an appendage and the body.
Any of the appendages of a decapod that are used for walking and gathering food.
Early, planktonic larval form common in decapod crustaceans, e.g., crabs, characterised by possession of well-developed abdominal appendages and one or more spines on the carapace.