Thymus serpyllum, known by the common names of Breckland thyme, wild thyme or creeping thyme, is a species of flowering plant in the mint family Lamiaceae, native to most of Europe and North Africa. It is a low, usually prostrate subshrub growing to 2 cm (1 in) tall with creeping stems up to 10 cm (4 in) long. The oval evergreen leaves are 3–8 mm long. The strongly scented flowers are either lilac, pink-purple, magenta, or a rare white, all 4–6 mm long and produced in clusters. The hardy plant tolerates some pedestrian traffic and produces odors ranging from heavily herbal to lightly lemon, depending on the plant.
Thymol and carvacrol, mentioned in literature as principial components, are not the main components of the essential oil of wild thyme growing in Estonia. (E)-nerolidol, caryophyllene oxide, myrcene and borneol chemotypes of wild thyme drug are distinguishable. The chemical composition of samples from Russia, Latvia and Armenia is very variable.