upstairs (adv.)

1590s, from up (adv.) + stairs (see stair). As an adjective from 1782. The noun is first attested 1872. Adjectival meaning "characteristic of upstairs life" (in private rooms of a household, as opposed to servants' quarters) is recorded from 1942.

He [Halifax] had said he had known many kicked down stairs, but he never knew any kicked up stairs before. [Gilbert Burnet, supplement to "History of My own Time," from his original memoirs, c. 1697]

updated on September 25, 2018

Definitions of upstairs from WordNet
upstairs (adv.)
on a floor above;
they lived upstairs
Synonyms: up the stairs / on a higher floor
upstairs (adv.)
with respect to the mind;
she's a bit weak upstairs
upstairs (n.)
the part of a building above the ground floor;
no one was allowed to see the upstairs
upstairs (adj.)
on or of upper floors of a building;
the upstairs maid
an upstairs room
Synonyms: upstair
Etymologies are not definitions. From, not affiliated with etymonline.