Marjoram, the common name of plants of the genus origanum, in the natural order la-biatte, having nearly entire leaves and purplish or whitish flowers crowded in cylindrical or oblong spikes, which are imbricated with frequently colored bracts. About 25 species are enumerated, of which the most common in the gardens is the sweet marjoram (O. majorana), native of Barbary and middle Asia. It is a clean, pretty, low, bushy plant, usually treated as an annual, but properly a perennial. The fragrant leaves and buds, being carefully dried, are pulverized by rubbing them in the hands, and are employed by cooks as a seasoning for forced-meat balls, stuffing, soups, etc. On account of the compact clusters or heads, it is in some localities known as knotted marjoram. The wild marjoram (0. vulgare) has become sparingly naturalized in the United States, adventitiously introduced from Europe. It can be found occasionally upon dry banks and sunny slopes. Its flowers are very pretty, appearing in the months of July and August. Essential oils may be extracted from either of the species mentioned above, but the oil which is now known in commerce as oil of origanum has heen shown to be really derived from the thymus vulgaris, a mint growing in the south of France. This is sometimes used as an external irritant, especially in veterinary practice, and, like many other volatile oils, will allay toothache when introduced into a carious cavity.
Internally it is a stimulant, but has no great value.