Ham"mer*head` (?), n.
1. Zool.
A shark of the genus Sphyrna or Zygaena, having the eyes set on projections from the sides of the head, which gives it a hammer shape. The Sphyrna zygaena is found in the North Atlantic. Called also hammer fish, and balance fish.
2. Zool.
A fresh-water fish; the stone-roller.
3. Zool.
An African fruit bat (Hypsignathus monstrosus); -- so called from its large blunt nozzle.
© Webster 1913.