1
general::
Phrase(s): take leave of someone or something
to go away from someone or something. • It is time for me to take leave of all of you. • It saddened me to take leave of the city I grew up in.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
1. Also, take one's leave of. Depart from, say good-bye to. For example, Sorry but I have to take leave of you now, or After the movie we'll take our leave of you. [Mid-1200s] 2. take leave of one's senses. Behave irrationally, act crazy, as in Give them the keys to the house? Have you taken leave of your senses? [Late 1800s] Also see COME TO ONE'S SENSES.
American Heritage Idioms