Sorrel (?), a. [F. saur, saure, OF. sor, sore, probably of Teutonic origin; cf. D. zoor dry, LG. soor; the meaning probably coming from the color of dry leaves. See Sear, a., and cf. Sorel.] Of a yellowish or redish brown color; as, a sorrel horse.
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Sorrel, n. [F. surelle, fr. sur sour, fr. OHG. s&unr_;r sour. See Sour.] (Bot.) One of various plants having a sour juice; especially, a plant of the genus Rumex, as Rumex Acetosa, Rumex Acetosella, etc.
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Mountain sorrel. (Bot.) See under Mountain. -- Red sorrel. (Bot.) (a) A malvaceous plant (Hibiscus Sabdariffa) whose acid calyxes and capsules are used in the West Indies for making tarts and acid drinks. (b) A troublesome weed (Rumex Acetosella), also called sheep sorrel. -- Salt of sorrel (Chem.), binoxalate of potassa; -- so called because obtained from the juice of Rumex Acetosella, or Rumex Axetosa. -- Sorrel tree (Bot.), a small ericaceous tree (Oxydendrum arboreum) whose leaves resemble those of the peach and have a sour taste. It is common along the Alleghanies. Called also sourwood. -- Wood sorrel (Bot.), any plant of the genus Oxalis.
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