The Collaborative International Dictionary of English v.0.48:

Saloon \Sa*loon"\ (s[.a]*l[=oo]n"), n. [F. salon (cf. It.
   salone), fr. F. salle a large room, a hall, of German or
   Dutch origin; cf. OHG. sal house, hall, G. saal; akin to AS.
   sael, sele, D. zaal, Icel. salr, Goth. saljan to dwell, and
   probably to L. solum ground. Cf. Sole of the foot, Soil
   ground, earth.]
   1. A spacious and elegant apartment for the reception of
      company or for works of art; a hall of reception, esp. a
      hall for public entertainments or amusements; a large room
      or parlor; as, the saloon of a steamboat.
      [1913 Webster]

            The gilden saloons in which the first magnates of
            the realm . . . gave banquets and balls. --Macaulay.
      [1913 Webster]

   2. Popularly, a public room for specific uses; esp., a
      barroom or grogshop; as, a drinking saloon; an eating
      saloon; a dancing saloon.
      [1913 Webster]

            We hear of no hells, or low music halls, or low
            dancing saloons [at Athens.]          --J. P.
                                                  Mahaffy.
      [1913 Webster]

WordNet (r) 3.0 (2006):

saloon
    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]
    2: tavern consisting of a building with a bar and public rooms;
       often provides light meals [syn: public house, pub,
       saloon, pothouse, gin mill, taphouse]
    3: a car that is closed and that has front and rear seats and
       two or four doors [syn: sedan, saloon]

Moby Thesaurus II by Grady Ward, 1.0:

57 Moby Thesaurus words for "saloon":
   Pullman car, alehouse, bar, barrel house, barroom, beer garden,
   beer parlor, best room, bistro, blind tiger, bucket shop, cabaret,
   cabin, cafe, cocktail lounge, cuddy, deckhouse, dive, dramshop,
   drawing room, drinkery, drinking saloon, foreroom, front room,
   gallery, gathering, gin mill, groggery, grogshop, hall, honky-tonk,
   house, living room, local, nightclub, parlor, parlor car, party,
   pothouse, pub, public, public house, rathskeller, roomette,
   rumshop, salon, saloon bar, shelter cabin, sitting room, solarium,
   speakeasy, stateroom, sun parlor, sunroom, taproom, tavern,
   wine shop