n. [ Tetra- + Gr. &unr_;, &unr_;, tooth. ] (Zool.) Any one of numerous species of plectognath fishes belonging to Tetrodon and allied genera. Each jaw is furnished with two large, thick, beaklike, bony teeth. [ Written also tetradon. ] [ 1913 Webster ]

☞ The skin is usually spinous, and the belly is capable of being greatly distended by air or water. It includes the swellfish, puffer (a), and similar species. [ 1913 Webster ]

a. (Zool.) Of or pertaining to the tetrodons. -- n. A tetrodon. [ Written also tetradont, and tetraodont. ] [ 1913 Webster ]