swellfish

A plectognath fish, of any of the several genera Tetrodon, Diodon, and related forms, capable of inflating itself like a ball, or swelling up by swallowing air: the name is given to the globe-fish, bur-fish, puffing-fish, porcupine-fish, rabbit-fish, tambor, puffer, etc.

Any plectognath fish that dilates itself, as the bur fish, puffer, or diodon.

Any plectognath fish that dilates itself, such as the pufferfish.