noun, na-adjective
Used in formal or written contexts to indicate a difference of opinion or a discrepancy. Often appears in compounds like 異議 (objection) or 異論 (different opinion).
両者の意見には異がある。
There is a difference of opinion between the two parties.
na-adjective
Describes something that deviates from the norm, often with a nuance of peculiarity. Commonly used in the adjectival noun form 異だ or 異な.
彼の行動は異だ。
His behavior is strange.
異な雰囲気を感じた。
I felt an unusual atmosphere.
prefix
Prefix used in compounds to mean 'different' or 'other', such as 異文化 (different culture) or 異世界 (another world). Not used as a standalone word in this sense.
異文化コミュニケーションは難しい。
Cross-cultural communication is difficult.