hammerhead shark

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Any of various sharks of the genus Sphyrna having the eyes set on projections from the sides of the head, which gives it a hammer shape.
• noun A winghead shark.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun medium-sized live-bearing shark with eyes at either end of a flattened hammer-shaped head; worldwide in warm waters; can be dangerous