Ennui is pronounced ahn-WEE (IPA /ɑːnˈwiː/). Two syllables — 'ahn-WEE' with stress on the second.
IPA: /ɑːnˈwiː/
Syllables: ahn · WEE
Common ESL mistake: Learners say 'EN-noo-ee' as three syllables.
Tip: Two syllables — 'ahn-WEE' with stress on the second.