n. [ Gr. di- = di`s- twice + 'odoy`s, 'odo`ntos, a tooth: cf. F. diodon. ] 1. (Zool.) A genus of spinose, plectognath fishes, having the teeth of each jaw united into a single beaklike plate. They are able to inflate the body by taking in air or water, and, hence, are called globefishes, swellfishes, etc. Called also porcupine fishes, and sea hedgehogs. [ 1913 Webster ]