downstairs

from WordNet (r) 3.0 (2006)

downstairs
    adv 1: on a floor below; "the tenants live downstairs" [syn:
           {downstairs}, {down the stairs}, {on a lower floor},
           {below}] [ant: {on a higher floor}, {up the stairs},
           {upstairs}]
    adj 1: on or of lower floors of a building; "the downstairs (or
           downstair) phone" [syn: {downstairs}, {downstair}] [ant:
           {upstair}, {upstairs}]

from The Collaborative International Dictionary of English v.0.48

downstair \downstair\, downstairs \downstairs\adj.
   on or of the lower floors of a building, especially the
   ground floor; as, the downstairs (or downstair phone; the
   house has no downstairs bathroom. Opposite of {upstairs}.
   [WordNet 1.5]

from The Collaborative International Dictionary of English v.0.48

downstairs \down"stairs\, adv.
   Down the stairs; to a lower floor; as, she headed downstairs
   as soon as she heard the horn.
   [1913 Webster +PJC]

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