The Collaborative International Dictionary of English v.0.48:

Ginger \Gin"ger\, n. [OE. ginger, gingever, gingivere, OF.
   gengibre, gingimbre, F. gingembre, L. zingiber, zingiberi,
   fr. Gr. ?; of Oriental origin; cf. Ar. & Pers. zenjeb[imac]l,
   fr. Skr. [,c][.r][.n]gav["e]ra, prop., hornshaped; ???ga horn
   + v["e]ra body.]
   [1913 Webster]
   1. (Bot.) A plant of the genus Zingiber, of the East and
      West Indies. The species most known is Zingiber
      officinale.
      [1913 Webster]

   2. The hot and spicy rootstock of Zingiber officinale,
      which is much used in cookery and in medicine.
      [1913 Webster]

   Ginger ale
      (a) a soft drink flavored with ginger and carbonated.
      (a) See ginger beer, below.

   Ginger beer or Ginger ale, a mild beer impregnated with
      ginger.

   Ginger cordial, a liquor made from ginger, raisins, lemon
      rind, and water, and sometimes whisky or brandy.

   Ginger pop. See Ginger ale (above).

   Ginger wine, wine impregnated with ginger.

   Wild ginger (Bot.), an American herb (Asarum Canadense)
      with two reniform leaves and a long, cordlike rootstock
      which has a strong taste of ginger.
      [1913 Webster]

WordNet (r) 3.0 (2006):

ginger ale
    n 1: ginger-flavored carbonated drink [syn: ginger ale,
         ginger pop]