Flavourful dried leaves and flowering tops of any of various perennial herbs of the mint family, particularly Origanum vulgare. Oregano is an essential ingredient of Mediterranean cuisines; in the U.S., use of oregano rose sharply in the late 20th century, largely because of the popularity of pizza. Native to the Mediterranean and western Asia, the herbs are now naturalized in parts of Mexico and the U.S.
Learn more about oregano with a free trial on Britannica.com.
The subspecies of oregano ''Origanum vulgare' is an important culinary herb. It is particularly widely used in Greek and Italian-American cuisines. It is the leaves that are used in cooking, and the dried herb is often more flavourful than the fresh..
Oregano is an indispensable ingredient for Greek cuisine. Oregano adds flavour to Greek salad and is usually used separately or added to the lemon-olive oil sauce that accompanies many fish or meat barbecues and some casseroles.
It has an aromatic, warm and slightly bitter taste. It varies in intensity; good quality is so strong that it almost numbs the tongue, but the cultivars adapted to colder climates have often unsatisfactory flavour. The influence of climate, season and soil on the composition of the essential oil is greater than the difference between the various species.
The related species Origanum onites (Greece, Asia Minor) and O. heracleoticum (Italy, Balkan peninsula, West Asia) have similar flavours. A closely related plant is marjoram from Asia Minor, which, however, differs significantly in taste, because phenolic compounds are missing in its essential oil. Some breeds show a flavour intermediate between oregano and marjoram.Pizza The dish most commonly associated with oregano is pizza. Its variations have probably been eaten in Southern Italy for centuries. Oregano became popular in the US when returning WWII soldiers brought back with them a taste for the “pizza herb”.
Oregano is high in antioxidant activity, due to a high content of phenolic acids and flavonoids. Additionally, oregano has demonstrated antimicrobial activity against food-borne pathogens such as Listeria monocytogenes. Both of these characteristics may be useful in both health and food preservation. In the Philippines, oregano (Coleus aromaticus) is not commonly used for cooking but is rather considered as a primarily medicinal plant, useful for relieving children's coughs.
Main constituents include carvacrol, thymol, limonene, pinene, ocimene, and caryophyllene. The leaves and flowering stems are strongly antiseptic, antispasmodic, carminative, cholagogue, diaphoretic, emmenagogue, expectorant, stimulant, stomachic and mildly tonic. Oregano is taken by mouth for the treatment of colds, influenza, mild fevers, indigestion, stomach upsets and painful menstruation. It is strongly sedative and should not be taken in large doses, though mild teas have a soothing effect and aid restful sleep. Used topically, oregano is one of the best herbal antiseptics because of its high thymol content
Hippocrates, the father of medicine, used oregano as an antiseptic as well as a cure for stomach and respiratory ailments. A Cretan oregano (O. dictamnus) is still used today in Greece to soothe a sore throat.
Several other plants are also known as oregano in various parts of Mexico, including Poliomintha longiflora, Lippia berlandieri, and Plectranthus amboinicus (syn. Coleus aromaticus), also called Cuban oregano.