The feeling of being out of one's usual environment.
The feeling of being out of one's usual environment — disorientation and unfamiliarity, which can be unsettling OR a welcome, refreshing change of scenery.
The experienced state of displacement — the “fish out of water” sensation — and notably ambivalent: it can alienate or pleasantly invigorate. It differs from Fernweh, which is a longing to be far away (a desire, not the experienced state), and from plain unease in being specifically about being away from the familiar.
dé- (privative) + pays “country” + -ment = roughly “being taken out of one's country.”
From dépayser (dé- “de-/dis-” + pays “country, region”) + -ment; dépaysé traces to Old French despaisier “to exile.”
From a literal removal from one's country (exile) toward the psychological feeling of unfamiliarity in any new environment, later acquiring the positive “refreshing change” reading. (A separate legal “change of venue” sense developed too.)
Popularly framed as “untranslatable,” which is overstated — “disorientation,” “culture shock,” and “change of scenery” each capture parts; its distinctiveness is bundling both the negative and positive readings in one word.