| Noun | 1. | genus Diodon - type genus of the Diodontidae fish genus - any of various genus of fish Diodontidae, family Diodontidae - spiny puffers Diodon hystrix, porcupine fish, porcupinefish - spines become erect when the body is inflated; worldwide in warm waters balloonfish, Diodon holocanthus - similar to but smaller than porcupinefish |