up·per¹ / ˈəpər/ • adj. 1. situated above another part: his upper arm the upper atmosphere. ∎  higher in position or status: the upper end of the social scale. 2. situated on higher ground. ∎  situated to the north: [in place names] Upper California. 3. Geol. & Archaeol. denoting a younger (and hence usually shallower) part of a stratigraphic division or archaeological deposit or the period in which it was formed or deposited: the Upper Paleolithic age.• n. 1. the part of a boot or shoe above the sole. 2. (uppers) upper dentures or teeth.PHRASES: have (or gain) the upper hand have or gain advantage or control over someone or something.up·per² • n. (usu. uppers) inf. a stimulating drug, esp. amphetamine.

upper upper room in the Bible, the room in which the Last Supper was celebrated, and in which the Holy Spirit descended to the disciples at Pentecost.
upper ten thousand the aristocracy; the term is first recorded in the US in 1844.

upper higher, top. XIV (not common before XV). f. UP + -ER3.
Hence sb. XIX, uppermost XV.