The Collaborative International Dictionary of English v.0.48:

Garlic \Gar"lic\, n. [OE. garlek, AS. g[=a]rle['a]c; gar spear,
   lance + le['a]c leek. See Gar, n., and Leek.]
   1. (Bot.) A plant of the genus Allium (A. sativum is the
      cultivated variety), having a bulbous root, a very strong
      smell, and an acrid, pungent taste. Each root is composed
      of several lesser bulbs, called cloves of garlic, inclosed
      in a common membranous coat, and easily separable.
      [1913 Webster]

   2. A kind of jig or farce. [Obs.] --Taylor (1630).
      [1913 Webster]

   Garlic mustard, a European plant of the Mustard family
      (Alliaria officinalis) which has a strong smell of
      garlic.

   Garlic pear tree, a tree in Jamaica (Crat[ae]va
      gynandra), bearing a fruit which has a strong scent of
      garlic, and a burning taste.
      [1913 Webster]

WordNet (r) 3.0 (2006):

garlic
    n 1: bulbous herb of southern Europe widely naturalized; bulb
         breaks up into separate strong-flavored cloves [syn:
         garlic, Allium sativum]
    2: aromatic bulb used as seasoning [syn: garlic, ail]

Easton's 1897 Bible Dictionary:

Garlic
   (Heb. shum, from its strong odour), mentioned only once (Num.
   11:5). The garlic common in Eastern countries is the Allium
   sativum or Allium Ascalonicum, so called from its having been
   brought into Europe from Ascalon by the Crusaders. It is now
   known by the name of "shallot" or "eschalot."