Downstairs

adv. on a lower floor

adj. situated on a lower floor

Stairs, staircase, stairway, and flight of stairs are all names for a construction designed to bridge a large vertical distance by dividing it into smaller vertical distances, called steps. Stairways may be straight, round, or may consist of two or more straight pieces connected at angles.Special stairways include escalators and ladders. Alternatives to stairways are elevators, stairlifts and inclined moving sidewalks.
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Adjective
1. on or of lower floors of a building; "the downstairs (or downstair) phone"
(synonym) downstair
(antonym) upstairs, upstair
(similar) ground-floor
Adverb
1. on a floor below; "the tenants live downstairs"
(synonym) down the stairs, on a lower floor, below
(antonym) upstairs, up the stairs, on a higher floor

(adv.)
Down the stairs; to a lower floor.
  

(a.)
Below stairs; as, a downstairs room.
  

The lower portion of the board, usually in reference to the 19s in a game of x01.