Ennui, n.
Etymology: [F., fr. L. in odio in hatred. See Annoy.]
A feeling of weariness and disgust; dullness and languor of spirits, arising from satiety or want of interest; tedium. T. Gray.
Shades of meaning
Fernald lists ennui only as an antonym, under entertainment.
He lists it without comment; the entries above explain its neighbors.
Synonyms
none given