ham·mer·head / ˈhamərˌhed/ • n. 1. (also hammerhead shark) a shark (genus Sphyrna, family Sphyrnidae) of tropical and temperate oceans that has flattened bladelike extensions on either side of the head, with the eyes and nostrils placed at or near the ends. 2. a brown African marsh bird (Scopus umbretta, family Scopidae) related to the storks, having a crest that looks like a backward projection of the head, and constructing an enormous nest. 3. the striking head of a hammer.

hammerhead Aggressive shark found in tropical marine waters and warmer temperate zones. It can be recognized by its head, which is extended sideways into two hammer-like lobes, with one eye and one nostril located at the tip of each. It is grey above and white below. Length: to 6.1m (20ft); weight: to 906kg (2000lb). Family Sphyrnidae.

hammerhead See SCOPIDAE.