Meaning of “given” - Learner’s Dictionary

given

adjective uk us /ˈɡɪvən/

[ always before noun ] already arranged or agreed:

They can only stay for a given amount of time.
any given day/time/week, etc

any day/time/week, etc:

About 4 million women are pregnant in the US at any given time.

(Definition of “given adjective” from the Cambridge Learner’s Dictionary © Cambridge University Press)