异域 is literary and atmospheric, evoking distance and exoticism. The neutral everyday term is 外国 (wàiguó, foreign country) or 国外 (guówài, abroad). 异域 is common in 异域风情 (yìyù fēngqíng, exotic flair) for tourism, food, and arts marketing.
memory
异 (different / strange) + 域 (region / territory) = "different region" → foreign / alien land. The 异 character implies otherness, not just geographic distance.
