1. The head of a hammer.
2. Any of several predatory sharks of the genus Sphyrna, having the sides of the head elongated into fleshy extensions with the eyes at the ends.
3. A wading bird (Scopus umbretta) of Africa and Arabia, having brown plumage, a large bladelike bill, and a long backward-pointing crest. Also called hamerkop.
4. An African fruit bat (Hypsignathus monstrosus), the male of which has a distinctive enlarged head.
(click for a larger image)hammerhead
scalloped hammerhead Sphyrna lewini
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