The word lime may refer to:
- Powdered chalk or limestone, consisting primarily of calcium carbonate, and often with calcium oxide, magnesium carbonate, or magnesium oxide, used in as a soil additive in agriculture to increase the pH (reduce the acidity) of soil.
- Calcium oxide ("burnt lime" or "quicklime")
- Various trees of the genus Citrus (especially Citrus latifolia) or their sour green or yellow fruits. See Lime (fruit).