Source : Webster's Revised Unabridged Dictionary (1913)

Bob \Bob\, v. i.
   1. To have a short, jerking motion; to play to and fro, or up
      and down; to play loosely against anything. ``Bobbing and
      courtesying.'' --Thackeray.

   2. To angle with a bob. See {Bob}, n., 2 & 3.

            He ne'er had learned the art to bob For anything but
            eels.                                 --Saxe.

   {To bob at an apple}, {cherry}, etc. to attempt to bite or
      seize with the mouth an apple, cherry, or other round
      fruit, while it is swinging from a string or floating in a
      tug of water.

Bob \Bob\, n. [An onomatopoetic word, expressing quick, jerky
   motion; OE. bob bunch, bobben to strike, mock, deceive. Cf.
   Prov. Eng. bob, n., a ball, an engine beam, bunch, blast,
   trick, taunt, scoff; as, a v., to dance, to courtesy, to
   disappoint, OF. bober to mock.]
   1. Anything that hangs so as to play loosely, or with a short
      abrupt motion, as at the end of a string; a pendant; as,
      the bob at the end of a kite's tail.

            In jewels dressed and at each ear a bob. --Dryden.

   2. A knot of worms, or of rags, on a string, used in angling,
      as for eels; formerly, a worm suitable for bait.

            Or yellow bobs, turned up before the plow, Are
            chiefest baits, with cork and lead enow. --Lauson.

   3. A small piece of cork or light wood attached to a fishing
      line to show when a fish is biting; a float.

   4. The ball or heavy part of a pendulum; also, the ball or
      weight at the end of a plumb line.

   5. A small wheel, made of leather, with rounded edges, used
      in polishing spoons, etc.

   6. A short, jerking motion; act of bobbing; as, a bob of the
      head.

   7. (Steam Engine) A working beam.

   8. A knot or short curl of hair; also, a bob wig.

            A plain brown bob he wore.            --Shenstone.

   9. A peculiar mode of ringing changes on bells.

   10. The refrain of a song.

             To bed, to bed, will be the bob of the song.
                                                  --L'Estrange.

   11. A blow; a shake or jog; a rap, as with the fist.

   12. A jeer or flout; a sharp jest or taunt; a trick.

             He that a fool doth very wisely hit, Doth very
             foolishly, although he smart, Not to seem senseless
             of the bob.                          --Shak.

   13. A shilling. [Slang, Eng.] --Dickens.

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}]

Source : Free On-Line Dictionary of Computing

Bob
     
        David Betz.  A tiny object-oriented language.
     
        {(ftp://ftp.mv.com/pub/ddj/packages/bob15.arc)}.
     
        [Dr Dobbs J, Sep 1991, p.26].