Source : Webster's Revised Unabridged Dictionary (1913)

Hammer \Ham"mer\, n. (Athletics)
   A spherical weight attached to a flexible handle and hurled
   from a mark or ring. The weight of head and handle is usually
   not less than 16 pounds.

Hammer \Ham"mer\, n. [OE. hamer, AS. hamer, hamor; akin to D.
   hamer, G. & Dan. hammer, Sw. hammare, Icel. hamarr, hammer,
   crag, and perh. to Gr. ? anvil, Skr. a?man stone.]
   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.

            With busy hammers closing rivets up.  --Shak.

   2. Something which in firm or action resembles the common
      hammer; as:
      (a) That part of a clock which strikes upon the bell to
          indicate the hour.
      (b) The padded mallet of a piano, which strikes the wires,
          to produce the tones.
      (c) (Anat.) The malleus. See under {Ear}. (Gun.) 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.
      (e) Also, a person of thing that smites or shatters; as,
          St. Augustine was the hammer of heresies.

                He met the stern legionaries [of Rome] who had
                been the ``massive iron hammers'' of the whole
                earth.                            --J. H.
                                                  Newman.

   {Atmospheric hammer}, a dead-stroke hammer in which the
      spring is formed by confined air.

   {Drop hammer}, {Face hammer}, etc. See under {Drop}, {Face},
      etc.

   {Hammer fish}. See {Hammerhead}.

   {Hammer hardening}, the process of hardening metal by
      hammering it when cold.

   {Hammer shell} (Zo["o]l.), any species of {Malleus}, a genus
      of marine bivalve shells, allied to the pearl oysters,
      having the wings narrow and elongated, so as to give them
      a hammer-shaped outline; -- called also {hammer oyster}.
      

   {To bring to the hammer}, to put up at auction.

Hammer \Ham"mer\, v. t. [imp. & p. p. {Hammered}; p. pr. & vb.
   n. {Hammering}.]
   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.
      ``Hammered money.'' --Dryden.

   3. To form in the mind; to shape by hard intellectual labor;
      -- usually with out.

            Who was hammering out a penny dialogue. --Jeffry.

Hammer \Ham"mer\, v. i.
   1. To be busy forming anything; to labor hard as if shaping
      something with a hammer.

            Whereon this month I have hammering.  --Shak.

   2. To strike repeated blows, literally or figuratively.

            Blood and revenge are hammering in my head. --Shak.

Source : WordNet®

hammer
     n 1: the part of a gunlock that strikes the percussion cap when
          the trigger is pulled [syn: {cock}]
     2: a hand tool with a heavy rigid head and a handle; used to
        deliver an impulsive force by striking
     3: an athletic competition in which a heavy metal ball that is
        attached to a flexible wire is hurled as far as possible
        [syn: {hammer throw}]
     4: the ossicle attached to the eardrum [syn: {malleus}]
     5: a heavy metal sphere attached to a flexible wire; used in
        the hammer throw
     6: a striker that is covered in felt and that causes the piano
        strings to vibrate
     7: a power tool for drilling rocks [syn: {power hammer}]
     8: the act of pounding (delivering repeated heavy blows); "the
        sudden hammer of fists caught him off guard"; "the
        pounding of feet on the hallway" [syn: {pound}, {hammering},
         {pounding}]

hammer
     v 1: beat with or as if with a hammer; "hammer the metal flat"
     2: create by hammering; "hammer the silver into a bowl"; "forge
        a pair of tongues" [syn: {forge}]

Source : Free On-Line Dictionary of Computing

hammer
     
        Commonwealth hackish synonym for {bang on}.
     
        [{Jargon File}]
     
        (1995-02-16)