| Noun | 1. | Dibranchia - comprising all living cephalopods except the family Nautilidae: the orders Octopoda (octopuses) and Decapoda (squids and cuttlefish) Cephalopoda, class Cephalopoda - octopuses; squids; cuttlefish; pearly nautilus Octopoda, order Octopoda - octopuses and paper nautilus Decapoda, order Decapoda - squids and cuttlefishes Belemnoidea, order Belemnoidea - order of extinct dibranchiate cephalopods related to the surviving spirulas class - (biology) a taxonomic group containing one or more orders |