THYMUS, in botany: A genus of plants belonging to the class of dianthus, and order of gynoecium; and in the natural system ranging under the 42nd order, Verbenaceae. The calyx is bilabiate, and its throat closed with soft hairs. There are 11 species; of which two only are natives of Britain, the serpyllum and acinos.

1. The serpyllum, or mother of thyme, has pale red flowers growing on round heads, terminal; the stalks are procumbent, and the leaves plane, obtuse, and ciliated at the base.

2. The acinos, or wild basil, has flowers growing in whorls on single leafstalks; the stalks are erect and branched; the leaves acute and serrated. The thymus vulgaris, or garden thyme, is a native of France, Spain, and Italy.—The attachment of bees to this and other aromatic plants is well known. In the experiments made at Upsal, sheep and goats were observed to eat it, and twine to refuse it.