Hypsignathus monstrosus

Hammerhead Ham"mer*head` (-h[e^]d`), n. 1. (Zo["o]l.) A shark of the genus {Sphyrna} or {Zyg[ae]na}, having the eyes set on projections from the sides of the head, which gives it a hammer shape. The {Sphyrna zyg[ae]na} is found in the North Atlantic. Called also {hammer fish}, and {balance fish}. [1913 Webster]

2. (Zo["o]l.) A fresh-water fish; the stone-roller. [1913 Webster]

3. (Zo["o]l.) An African fruit bat ({Hypsignathus monstrosus}); -- so called from its large blunt nozzle. [1913 Webster]