Definition of: lemon

(lem′ən) noun
1. An oval citrus fruit with a bright–yellow skin containing the essential oil of lemon, and very acid pulp and juice.
2. The small or medium–sized evergreen tree (Citrus medica and C. lemon) of the rue family that produces this fruit.
3. The color of the rind of lemon; bright yellow.
4. U. S. Slang Something disappointing, worthless. or unpleasant.
—adjective
1. Flavored with or containing lemon: lemon pie.
2. Lemon–colored. [<OF limon <Sp. limón <Arabic laimūn <Persian līmūn. Related to LIME².]