Liquorice (British English) or licorice (American English) LIK-(ə-)rish, LIK-(ə-)ris) is the root of Glycyrrhiza glabra from which a sweet flavour can be extracted. The liquorice plant is a herbaceous perennial legume native to southern Europe and parts of Asia, such as India. It is not botanically related to anise, star anise, or fennel, which are sources of similar flavouring compounds.

Most liquorice is used as a flavouring agent for tobacco, particularly US blend cigarettes, to which liquorice lends a natural sweetness and a distinctive flavour and makes it easier to inhale the smoke by creating bronchodilators, which open up the lungs. Liquorice flavours are also used as candies or sweeteners, particularly in some European and Middle Eastern countries. Liquorice extracts have a number of medical uses, and they are also used in herbal and folk medications. Excessive consumption of liquorice (more than 2 mg/kg/day of pure glycyrrhizinic acid, a liquorice component) may result in adverse effects, and overconsumption should be suspected clinically in patients presenting with otherwise unexplained hypokalemia and muscle weakness.