Definition of unhappiness:
dejection, desolation, doldrums, miserableness, mopes, mournfulness, glumness, feelings, depression, blue devils, sadness, disconsolateness, lugubriousness, mope, dreariness, grief, forlornness, dolefulness, heavy-heartedness, despond, downheartedness, dispiritedness, gloom, oppression, woe, blues, depression, sorrow, melancholy, sorrowfulness, funk, heartsickness, dumps, happy, dysphoria, despondency.
discontentment (part of speech: noun)
- "The Duke's Children", Anthony Trollope.
- "The Bertrams", Anthony Trollope.
- "A Beautiful Alien", Julia Magruder.