Synonyms for Ennui:

n.

cabin fever, the doldrums, disinterest, torpor. excite. apathy (noun)
languor.
boredom (noun)
depression, dissatisfaction, weariness, fatigue, sadness, monotony, melancholy, apathy, indifference, dejection, blues, dullness, listlessness, tedium, languor.
dejection (noun)
discouragement, disheartenment, moodiness, glumness, contemplativeness, dejection, pensiveness, moroseness, dolorousness, mournfulness, wistfulness, woefulness, sullenness, despondency, dreariness, dispiritedness, despair, melancholy, depression, downheartedness, plaintiveness, blues, sadness, grimness.
depression (noun)
dispiritedness, cheerlessness, gloominess, dreariness, woefulness.
discontentment (noun)
discomfort, non-satisfaction, boredom, disgruntlement, sourness, angst, anguish, discontent, dissatisfaction, cheerlessness, irritation, misery, despondence, gloominess, disquiet, discomposure, unhappiness, displeasure, wretchedness, anxiety, joylessness, inquietude, uneasiness, uncomfortableness, frustration, exasperation.
ennui (noun)
tedium, the doldrums, tiredness, languor, boredom, listlessness, dissatisfaction.
fatigue (noun)
faintness.
unrest (noun)
moodiness.
weariness (noun)
debilitation, tiredness, fatigue, over-weariness, exhaustion, weariness, sleepiness, feebleness, flaccidity, footsoreness, drowsiness, weakness, faintness, droopiness.

Other synonyms:

cabin fever, the doldrums, disinterest, torpor. Other relevant words:
torpor, excite, disinterest, languor.

Usage examples for ennui

  1. It was only to her closest intimates that she honestly acknowledged herself to be tortured by ennui – Democracy An American Novel by Henry Adams
  2. It proved that my dearest demands from life, namely, my demands for vanity, and diversion from ennui arose directly from my idle life. – On the Significance of Science and Art from What to Do? by Count Lyof N. Tolstoi