Source : Webster's Revised Unabridged Dictionary (1913)

Bob \Bob\, v. t. [imp. & p. p. {Bobbed}; p. pr. & vb. n.
   {Bobbing}.] [OE. bobben. See {Bob}, n.]
   1. To cause to move in a short, jerking manner; to move (a
      thing) with a bob. ``He bobbed his head.'' --W. Irving.

   2. To strike with a quick, light blow; to tap.

            If any man happened by long sitting to sleep . . .
            he was suddenly bobbed on the face by the servants.
                                                  --Elyot.

   3. To cheat; to gain by fraud or cheating; to filch.

            Gold and jewels that I bobbed from him. --Shak.

   4. To mock or delude; to cheat.

            To play her pranks, and bob the fool, The shrewish
            wife began.                           --Turbervile.

   5. To cut short; as, to bob the hair, or a horse's tail.

Source : WordNet®

bob
     n 1: a former monetary unit in Great Britain [syn: {British
          shilling}, {shilling}]
     2: a hair style for women and children; a short haircut all
        around
     3: a long racing sled (for 2 or more people) with a steering
        mechanism [syn: {bobsled}, {bobsleigh}]
     4: a hanging weight, especially a metal ball on a string
     5: a small float usually made of cork; attached to a fishing
        line [syn: {bobber}, {cork}, {bobfloat}]
     6: a short or shortened tail of certain animals [syn: {bobtail},
         {dock}]
     7: a short abrupt inclination (as of the head); "he gave me a
        short bob of acknowledgement"
     [also: {bobbing}, {bobbed}]

bob
     v 1: move up and down repeatedly; "her rucksack bobbed gently on
          her back"
     2: ride a bobsled; "The boys bobbed down the hill screaming
        with pleasure" [syn: {bobsled}]
     3: remove or shorten the tail of an animal [syn: {dock}, {tail}]
     4: make a curtsy; usually done only by girls and women; as a
        sign of respect; "She curtsied when she shook the Queen's
        hand" [syn: {curtsy}]
     5: cut hair in the style of a bob; "Bernice bobs her hair these
        days!"
     [also: {bobbing}, {bobbed}]

bobbed
     See {bob}