Source : Webster's Revised Unabridged Dictionary (1913)

Lavatory \Lav"a*to*ry\, n.; pl. {Lavatories}. [L. lavatorium:
   cf. lavatoire. See {Lave} to wash, and cf. {Laver}.]
   1. A place for washing.

   2. A basin or other vessel for washing in.

   3. A wash or lotion for a diseased part.

   4. A place where gold is obtained by washing.

Lavatory \Lav"a*to*ry\, a.
   Washing, or cleansing by washing.

Source : WordNet®

lavatory
     n 1: a room equipped with toilet facilities [syn: {toilet}, {lav},
           {can}, {john}, {privy}, {bathroom}]
     2: a bathroom or lavatory sink that is permanently installed
        and connected to a water supply and drainpipe; where you
        wash your hands and face; "he ran some water in the basin
        and splashed it on his face" [syn: {washbasin}, {basin}, {washbowl},
         {washstand}]
     3: a toilet that is cleaned of waste by the flow of water
        through it [syn: {flush toilet}]