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ham·mer·head

(hămər-hĕd′)

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.

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hammerhead

scalloped hammerhead Sphyrna lewini

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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