HAMMERER
Ham"mer*er, n.

Defn: One who works with a hammer.

HAMMER-HARDEN
Ham"mer-hard`en, v. t.

Defn: To harden, as a metal, by hammering it in the cold state.

HAMMERHEAD
Ham"mer*head`, n.

1. (Zoöl.)

Defn: A shark of the genus Sphyrna or Zygæna, having the eyes set on projections from the sides of the head, which gives it a hammer shape. The Sphyrna zygæna is found in the North Atlantic. Called also hammer fish, and balance fish.

2. (Zoöl.)

Defn: A fresh-water fish; the stone-roller.

3. (Zoöl.)