What does “산전수전” mean in Korean?

산전수전 is a four-character idiom (사자성어) built from 山戰 (mountain battle) and 水戰 (water battle) — fights waged on every kind of terrain. Together they mean having survived all sorts of hardship: every up, down, and ordeal life can throw at you. It’s the Korean way of saying someone has truly “been through it all” and come out seasoned by it.

It almost always rides with the verb 겪다 (“to go through”): 산전수전 다 겪다 — “to have been through every hardship,” and 산전수전 다 겪은 베테랑 is “a veteran who’s seen it all.” Each half is itself a Sino-Korean word built from 戰 (war/battle), the giveaway that this is a 사자성어 borrowed from Chinese. Here an older man reassures the self-conscious eighteen-year-old with it: 산전수전 겪다 보면 얼굴이 변해요 — “once you’ve been through it all, your face changes.”