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]
〔李〕[up-=up在⋯上；stairs n.楼梯 →] a. ＆ ad.up the stairs在楼上（的）