Meaning of “function” - Learner’s Dictionary

function

noun [ C ] us uk /ˈfʌŋkʃən/
PURPOSE

B2 the purpose of something or someone:

Each button has a different function.
I'm not quite sure what my function is within the company.

More examples

EVENT

a large, formal party or ceremony:

a charity function

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