lem·on 
(lĕmən)
(lĕmən)n.
1.
a. A spiny evergreen tree (Citrus limon) native to Asia, widely cultivated for its oval yellow fruit.
b. The fruit of this tree, having an aromatic rind and juicy, acid pulp.
2. Lemon yellow.
3. Informal One that is unsatisfactory or defective: Their new car turned out to be a lemon.
adj.
1. Lemon-yellow.
2.
a. Made from lemons.
b. Tasting or smelling like lemons.
[Middle English limon, from Old French, from Old Italian limone, from Arabic laymūn, ultimately from alteration (probably influenced by an Andalusian Romance augmentative suffix akin to Spanish -ón) of Persian līmū, lemon, any of various citrus fruits; see LIME.]
lemon·y adj.