The Collaborative International Dictionary
Ostracion
Ostracion \Os*tra"ci*on\, prop. n. [NL., fr. Gr. 'ostra`kion small shell.] (Zo["o]l.) A genus of plectognath fishes of the family Ostraciontidae having the body covered with solid, immovable, bony plates. It includes the trunkfishes (also called boxfish).
Wikipedia
Usage examples of "ostracion".
I shall notice chiefly ostracions peculiar to the Red Sea, the Indian Ocean, and that part which washes the coast of tropical America.
I would also mention quadrangular ostracions, having on the back four large tubercles.