The Collaborative International Dictionary of English v.0.48:

Beer \Beer\, n. [OE. beor, ber, AS. be['o]r; akin to Fries.
   biar, Icel. bj?rr, OHG. bior, D. & G. bier, and possibly E.
   brew. [root]93, See Brew.]
   1. A fermented liquor made from any malted grain, but
      commonly from barley malt, with hops or some other
      substance to impart a bitter flavor.
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   Note: Beer has different names, as small beer, ale,
         porter, brown stout, lager beer, according to its
         strength, or other qualities. See Ale.
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   2. A fermented extract of the roots and other parts of
      various plants, as spruce, ginger, sassafras, etc.
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   Small beer, weak beer; (fig.) insignificant matters. "To
      suckle fools, and chronicle small beer." --Shak.
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WordNet (r) 3.0 (2006):

beer
    n 1: a general name for alcoholic beverages made by fermenting a
         cereal (or mixture of cereals) flavored with hops