Source : Webster's Revised Unabridged Dictionary (1913)

Limelight \Lime"light`\, n. (Theat.)
   That part of the stage upon which the limelight as cast,
   usually where the most important action is progressing or
   where the leading player or players are placed and upon which
   the attention of the spectators is therefore concentrated.
   Hence, consspicuous position before the public; as,
   politicians who are never happy except in the limelight.

Source : WordNet®

limelight
     n 1: a focus of public attention; "he enjoyed being in the
          limelight"; "when Congress investigates it brings the
          full glare of publicity to the agency" [syn: {spotlight},
           {glare}, {public eye}]
     2: a lamp consisting of a flame directed at a cylinder of lime
        with a lens to concentrate the light; formerly used for
        stage lighting [syn: {calcium light}]