Tra từ upper - Từ điển Oxford Advanced Learner 8th

upper [upper uppers] adjective, noun BrE [ˈʌpə(r)] NAmE [ˈʌpər]
adjective only before noun
1. located above sth else, especially sth of the same type or the other of a pair
•the upper lip
•the upper deck
2. at or near the top of sth
•the upper arm
•the upper slopes of the mountain
•a member of the upper middle class
•salaries at the upper end of the pay scale
• There is an upper limit of £20 000 spent on any one project.
3. (of a place)located away from the coast, on high ground or towards the north of an area
•the upper reaches of the river
Opp: ↑lower
more at a stiff upper lip at ↑stiff _adj.

Word Origin:
adj. and n. sense 1 Middle English ↑up ↑-ern. sense 2 1960s ↑up ↑-er
Idioms: gain/get/have the upper hand ▪ ↑on your uppers

noun usually plural
1. the top part of a shoe that is attached to the ↑sole
•shoes with leather uppers
2. (informal)a drug that makes you feel excited and full of energy
compare ↑downer

Word Origin:
adj. and n. sense 1 Middle English ↑up ↑-ern. sense 2 1960s ↑up ↑-er