Borrowed from French ennui, from Old French enui (“annoyance”), from enuier (modern French ennuyer), from Late Latin inodiō, from Latin in odiō (“hated”). Doublet of annoy.
ennui (countable and uncountable, plural ennuis)
- A gripping listlessness or melancholia caused by boredom; depression.
ennui (third-person singular simple present ennuis, present participle ennuying, simple past and past participle ennuied or ennuyed)
- (transitive) To make bored or listless; to weary.