- the yellowish, acid fruit of a subtropical citrus tree, Citrus limon.
- the tree itself.
- lemon yellow.
- Informal. a person or thing that proves to be defective, imperfect, or unsatisfactory; dud: His car turned out to be a lemon.
- made of or with lemon.
- having the color, taste, or odor of lemon.
- a small Asian evergreen tree, Citrus limon, widely cultivated in warm and tropical regions, having pale green glossy leaves and edible fruitsRelated adjectives: citric, citrine, citrous
- the yellow oval fruit of this tree, having juicy acidic flesh rich in vitamin C
- (as modifier)a lemon jelly
- Also called: lemon yellow
- a greenish-yellow or strong yellow colour
- (as adjective)lemon wallpaper
- a distinctive tart flavour made from or in imitation of the lemon
- slang a person or thing considered to be useless or defective
n.1type of citrus fruit, c.1400, lymon, from Old French limon “citrus fruit” (12c.), via Provençal or Italian from Arabic laimun, from Persian limu(n), generic terms for citrus fruits (cf. lime (n.2)); cognate with Sanskrit nimbu “the lime.” Slang meaning “a Quaalude” is 1960s, from Lemmon, name of a pharmaceutical company that once manufactured the drug. n.2“worthless thing,” 1909, American English slang; from lemon (n.1), perhaps via criminal slang sense of “a person who is a loser, a simpleton,” which is perhaps from the notion of someone a sharper can “suck the juice out of.” A pool hall hustle was called a lemon game (1908); while to hand someone a lemon was British slang (1906) for “to pass off a sub-standard article as a good one.” Or it simply may be a metaphor for something which leaves a bad taste in one’s mouth.