upper · adjective always before noun /ˈʌp.ər/Full view
B1 at a higher position or level than something else
Dictionary examples:

the upper lip/body

The office block's upper floors were being repainted.

Learner example:

I am doing the upper intermediate level and last summer I was in London [for] three months. (First Certificate in English; B2; Spanish)

the upper limit
C2 the highest amount or level, or the longest time that something is allowed
Dictionary example:

£45,000 is the upper limit for salaries in this job.

Learner example:

I understand that it will be more expensive than the accom[m]odation I currently have, and I am willing to stretch the upper limit of the rent I can afford to pay. (International English Language Testing System; C2; Hindi)

get/gain the upper hand
C2 to get into a stronger position than someone else so that you are controlling a situation
Dictionary example:

Government troops are gradually gaining the upper hand over the rebels.

Learner example:

He knew that Hooper had got the upper hand and that there was no escape. (Certificate of Proficiency in English; C2; Greek)

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