lemon

The lemon tree and its fruit. The juice of the lemon fruit contains about four times as much citric acid as is found in the orange. It is a major commercial source of citric acid.

Sharp-tasting yellow citrus fruit of the small, evergreen, semitropical lemon tree. It may have originated in northwestern India, and was introduced into Europe by the Spanish Moors in the 12th or 13th century. It is now grown in Italy, Spain, California, Florida, South Africa, and Australia, and is widely used for flavouring and as a garnish. (Citrus limon, family Rutaceae.)