1. An instrument for driving nails, beating metals, and the like, consisting of a head, usually of steel or iron, fixed crosswise to a handle.
  2. Something which in firm or action resembles the common hammer
  3. That part of a clock which strikes upon the bell to indicate the hour.
  4. The padded mallet of a piano, which strikes the wires, to produce the tones.
  5. The malleus.
  6. That part of a gunlock which strikes the percussion cap, or firing pin; the cock; formerly, however, a piece of steel covering the pan of a flintlock musket and struck by the flint of the cock to ignite the priming.
  7. Also, a person of thing that smites or shatters; as, St. Augustine was the hammer of heresies.

v. t.

  1. To beat with a hammer; to beat with heavy blows; as, to hammer iron.
  2. To form or forge with a hammer; to shape by beating.
  3. To form in the mind; to shape by hard intellectual labor; -- usually with out.

v. i.

  1. To be busy forming anything; to labor hard as if shaping something with a hammer.
  2. To strike repeated blows, literally or figuratively.