The Collaborative International Dictionary of English v.0.48:

Barroom \Bar"room`\, n.
   1. A room containing a bar or counter at which liquors are
      sold.
      [1913 Webster]

   2. a commercial establishment where alcoholic drinks are
      served over a counter.

   Syn: bar-room, bar, saloon, ginmill, taproom.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

barroom
    n 1: a room or establishment where alcoholic drinks are served
         over a counter; "he drowned his sorrows in whiskey at the
         bar" [syn: barroom, bar, saloon, ginmill,
         taproom]

Moby Thesaurus II by Grady Ward, 1.0:

33 Moby Thesaurus words for "barroom":
   alehouse, bar, barrel house, beer garden, beer parlor, bistro,
   blind tiger, cabaret, cafe, cocktail lounge, dive, dramshop,
   drinkery, drinking saloon, gin mill, groggery, grogshop,
   honky-tonk, local, lounge, nightclub, pothouse, pub, public,
   public house, rathskeller, rumshop, saloon, saloon bar, speakeasy,
   taproom, tavern, wine shop