Meaning of “departure” - Learner’s Dictionary

departure

noun [ C, U ] uk us /dɪˈpɑːtʃər/
LEAVING

B1 the act of leaving a place, especially to start a journey to another place:

the departure of flight BA117
This fare is valid for weekday departures from Manchester.
CHANGE

a change from what is expected, or from what has happened before:

This film is a major departure from his previous work.

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