いずれか

A formal pronoun meaning "one of" or "either one" from a set of options. More literary and formal than どれか or どちらか. Often used in written documents, contracts, and official instructions.

Common patterns

• いずれかの + noun: one of the ~
• いずれかを選(えら)ぶ: to choose one or the other
• いずれかに該当(がいとう)する: to fall under one of

Similar words

• どれか — which one (casual, general)
• どちらか — one of two (polite but less formal than いずれか)
• いずれも — all of them; every one (contrasts with いずれか which selects one)