citron

n. [ F. citron, LL. citro, fr. L. citrus citron tree (cf. citreum, sc. malum, a citron), from Gr. ki`tron citron ] 1. (Bot) A fruit resembling a lemon, but larger, and pleasantly aromatic; it is produced by the citron tree (Citrus medica). The thick rind, when candied, is the citron of commerce. The fruit was once called the lime. [ 1913 Webster ]

2. A citron tree, Citrus medica. [ 1913 Webster ]

3. A citron melon. [ 1913 Webster ]

Citron melon. (a) A small variety of muskmelon with sugary greenish flesh. (b) A small variety of watermelon, whose solid white flesh is used in making sweetmeats and preserves. --
Citron tree (Bot.), the tree which bears citrons. It was probably a native of northern India, and is now understood to be the typical form of Citrus Medica. [ 1913 Webster ]