Meaning of “excuse” - Learner’s Dictionary

excuse

noun [ C ] uk us /ɪkˈskjuːs/
REASON

B1 a reason that you give to explain why you did something wrong:

[ + for + doing sth ] I hope he's got a good excuse for being so late.
FALSE REASON

B1 a false reason that you give to explain why you do something:

Nick was just looking for an excuse to call her.

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