Source : Webster's Revised Unabridged Dictionary (1913)

Knob \Knob\, n. [A modification of knop. Cf. {Nob}.]
   1. A hard protuberance; a hard swelling or rising; a bunch; a
      lump; as, a knob in the flesh, or on a bone.

   2. A knoblike ornament or handle; as, the knob of a lock,
      door, or drawer. --Chaucer.

   3. A rounded hill or mountain; as, the Pilot Knob. [U. S.]
      --Bartlett.

   4. (Arch.) See {Knop}.

   {Knob latch}, a latch which can be operated by turning a
      knob, without using a key.

Knob \Knob\, v. i.
   To grow into knobs or bunches; to become knobbed. [Obs.]
   --Drant.

Source : WordNet®

knob
     n 1: a circular rounded projection or protuberance [syn: {boss}]
     2: a round handle
     3: any thickened enlargement [syn: {node}, {thickening}]
     4: an ornament in the shape of a ball on the hilt of a sword or
        dagger [syn: {pommel}]
     [also: {knobbing}, {knobbed}]