running away from home for a very short time; petit runaway
A casual, modern term for a brief, often impulsive, escape from home, typically lasting only a few hours or a day, without serious intent to leave permanently. Contrasts with 家出, which implies a longer or more serious departure.
See also: 家出
昨日、ちょっとしたことでプチ家出をした。
Yesterday, I ran away from home for a little while over something trivial.
プチ家出から数時間後に、自分から家に戻った。
A few hours after my petit runaway, I came back home on my own.
Combination of プチ (from French 'petit', meaning small or little) and 家出 (running away from home). The exact origin is uncertain, but it likely emerged in casual Japanese as a playful way to describe a minor, short-lived runaway episode.