noun, plural (especially collectively) por·cu·pine·fish, (especially referring to two or more kinds or species) por·cu·pine·fish·es.

any of several fishes of the family Diodontidae, especially Diodon hystrix, of tropical seas, capable of inflating the body with water or air until it resembles a globe, with erection of the long spines covering the skin.

Origin of porcupinefish

First recorded in 1675–85; porcupine + fish
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019