Se faire la malle

Literally: To make oneself the trunk

Example: “Le chat s'est fait la malle par la fenêtre de la cuisine.” — The cat flew the coop through the kitchen window.

English equivalent: To fly the coop

Origin: A malle is the trunk you pack for a journey, and faire sa malle — to pack it — was once ordinary language for preparing to travel. The reflexive twist appears around 1935, of a prisoner escaping, and is built like the slang se faire la belle and se faire la paire: the escapee has figuratively gone on a trip, and so has taken his trunk with him, however unlikely it is that he stopped to pack. The word has a grim history in these phrases. In the 16th century trousser en malle meant to carry off by surprise; by the 17th, troussé en malle meant dead, which suggests how those carryings-off usually ended. Plier sa malle meant to die at the end of the 17th century and faire sa malle meant the same by the end of the 19th, and at just the moment our expression appears, faire la malle à quelqu'un meant to walk out on them.