\Lem"on\ (l[e^]m"[u^]n), n. [F. limon, Per. l[imac]m[=u]n;
cf. Ar. laim[=u]n, Sp. limon, It. limone. Cf. {Lime} a
fruit.]
1. (Bot.) An oval or roundish fruit resembling the orange,
   and containing a pulp usually intensely acid. It is
   produced by a tropical tree of the genus {Citrus}, the
   common fruit known in commerce being that of the species
   {C. Limonum} or {C. Medica} (var. Limonum). There are many
   varieties of the fruit, some of which are sweet.
2. The tree which bears lemons; the lemon tree.
{Lemon grass} (Bot.), a fragrant East Indian grass
   ({Andropogon Sh[oe]nanthus}, and perhaps other allied
   species), which yields the grass oil used in perfumery.
{Lemon sole} (Zo["o]l.), a yellow European sole ({Solea
   aurantiaca}).
{Salts of lemon} (Chem.), a white crystalline substance,
   inappropriately named, as it consists of an acid potassium
   oxalate and contains no citric acid, which is the
   characteristic acid of lemon; -- called also {salts of
   sorrel}. It is used in removing ink stains. See {Oxalic
   acid}, under {Oxalic}. [Colloq.]