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.

Source: Webster's Revised Unabridged Dictionary (1913)
 

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.

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.

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: Webster's Revised Unabridged Dictionary (1913)