French leave

noun

: an informal, hasty, or secret departure

But as I was certain I should not be allowed to leave the enclosure, my only plan was to take French leave and slip out when nobody was watching …

—Robert Louis Stevenson

The best sign that a husband is not about to take French Leave is a clear demonstration that he still loves his wife …

—John O'Sullivan

In the middle of the world premiere of his latest film, "Seklusyon," at the Galaxy Cinemas last Sunday, filmmaker Erik Matti had to take a French leave and rushed to another event …

—Bayani San Diego, Jr.

Word History

Etymology

from an 18th century French custom of leaving a reception without taking leave of the host or hostess

First Known Use

1748, in the meaning defined above