Source : Webster's Revised Unabridged Dictionary (1913)

Drinker \Drink"er\, n.
   One who drinks; as, the effects of tea on the drinker; also,
   one who drinks spirituous liquors to excess; a drunkard.

   {Drinker moth} (Zo["o]l.), a large British moth ({Odonestis
      potatoria}).

Source : WordNet®

drinker
     n 1: a person who drinks liquids
     2: a person who drinks alcoholic beverages (especially to
        excess) [syn: {imbiber}, {toper}, {juicer}] [ant: {abstainer}]