—adj. 1. having a harsh, disagreeably acrid taste, like that of aspirin, quinine, wormwood, or aloes.
2. producing one of the four basic taste sensations; not sour, sweet, or salt.
3. hard to bear; grievous; distressful: a bitter sorrow. 4. causing pain; piercing; stinging: a bitter chill. 5. characterized by intense antagonism or hostility: bitter hatred. 6. hard to admit or accept: a bitter lesson. 7. resentful or cynical: bitter words.
—n. 1. that which is bitter; bitterness: Learn to take the bitter with the sweet. 2. Brit.a very dry ale having a strong taste of hops.
—v.t. to make bitter: herbs employed to bitter vermouth.
—adv. extremely; very; exceedingly: a bitter cold night.