sour

Short definition from Wiktionary

Adjective

1. 1
   Tasting of acidity.
2. 2
   Made rancid by fermentation, etc.
3. 3
   Tasting or smelling rancid.
4. 4
   Hostile or unfriendly.
5. 5
   Excessively acidic and thus infertile. (of soil)
6. 6
   Containing excess sulfur. (of petroleum)
7. 7
   Unfortunate or unfavorable.
8. 8
   Off-pitch, out of tune.

Noun

1. 1
   The sensation of a sour taste.
2. 2
   A drink made with whiskey, lemon or lime juice and sugar.
3. 3
   Any cocktail containing lemon or lime juice.
4. 4
   A sweet/candy having a sharply sour taste.
5. 5
   A sour or acid substance; whatever produces a painful effect.
6. 6
   The acidic solution used in souring fabric.

Verb

1. 1
   To make sour.
2. 2
   To become sour.
3. 3
   To spoil or mar; to make disenchanted.
4. 4
   To become disenchanted.
5. 5
   To make (soil) cold and unproductive.
6. 6
   To macerate (lime) and render it fit for plaster or mortar.
7. 7
   To process (fabric) after bleaching, using hydrochloric acid or sulphuric acid to wash out the lime.