noun, noun which may take the genitive case particle 'no'
unforeseen occurrence; unexpected event; accident
Rare literary term for an unforeseen or accidental event. Cross-referenced with 不慮, which is the common modern equivalent.
See also: 不慮
「不虞」は古い文章で不慮の出来事を指すことがある。
In old writing, 不虞 can refer to an unforeseen event.