The Collaborative International Dictionary of English v.0.48:

lime light \lime" light`\, limelight \lime"light`\
   An intense light produced by heating lime. See Calcium
   light under Calcium.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

limelight \lime"light`\, n. (Theat.)
   That part of the stage upon which the limelight is 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, a conspicuous position before the public; the center
   of public attention; -- used mostly in the phrase in the
   limelight; as, politicians who are never happy except in the
   limelight.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

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: limelight,
         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: limelight, calcium light]

Moby Thesaurus II by Grady Ward, 1.0:

48 Moby Thesaurus words for "limelight":
   PR, arc, arc light, ballyhoo, blurb, bright light, celebrity,
   color filter, common knowledge, cry, currency, daylight, dimmer,
   eclat, exposure, fame, famousness, floats, flood, floodlight,
   footlights, foots, gelatin, glare, hoopla, hue and cry,
   klieg light, light plot, lights, marquee, maximum dissemination,
   medium, notoriety, plug, press notice, public eye,
   public knowledge, public relations, public report, publicity,
   publicity story, publicness, puff, reclame, report, spot,
   spotlight, write-up