hammerhead

American  

[ham-er-hed] / ˈhæm ərˌhɛd /

noun

1. the part of a hammer designed for striking.

2. a shark of the genus Sphyrna, especially S. zygaena, having the head expanded laterally so as to resemble a double-headed hammer, sometimes dangerous to swimmers.

3. Also called hammerkop.  a brown heronlike African bird, Scopus umbretta, having the head so crested as to resemble a claw hammer.

4. flatheaded borer.

5. Slang. blockhead; dunce; lout.

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hammerhead British  

/ ˈhæməˌhɛd /

noun

1. any shark of the genus Sphyrna and family Sphyrnidae, having a flattened hammer-shaped head

2. a heavily built tropical African wading bird, Scopus umbretta, related to the herons, having a dark plumage and a long backward-pointing crest: family Scopidae, order Ciconiiformes

3. a large African fruit bat, Hypsignathus monstrosus, with a large square head and hammer-shaped muzzle

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Other Word Forms

• hammerheaded
  adjective

Etymology

Origin of hammerhead

First recorded in 1525–35; hammer + head

Example Sentences

So instead of getting swept away by the narrative, I just settled in to enjoy the details: hammerhead sharks twisted into pickaxes, ships that scuttle like crabs, the drama of an underwater scream: “Guh-glurrgggh!”

From Los Angeles Times • Dec. 16, 2025

This includes groups of special sharks, such as endangered hammerhead sharks and whale sharks.

From NewsForKids.net • Apr. 2, 2024

These new variants performed similarly, but their mutations made them easier to replicate, which increased their evolutionary fitness and led them to eventually dominate the lab's hammerhead population.

From Science Daily • Mar. 4, 2024

Kaneohe Bay is home to coral reefs, an ancient Hawaiian fishpond and a breeding ground for hammerhead sharks.

From Seattle Times • Nov. 27, 2023

“Has anyone ever told you and your friends that you remind them of great hammerhead sharks?”

From "Shouting at the Rain" by Lynda Mullaly Hunt