See blues in Webster's New World Roget's A-Z Thesaurus II
A feeling or spell of dismally low spirits:
dejection, depression, despondence, despondency, doldrums, dolefulness, downheartedness, dumps, dysphoria, funk, gloom, glumness, heavy-heartedness, melancholy, mope (used in plural), mournfulness, sadness, unhappiness. See feelings, happyLearn more about blues