Citrus is a genus of plants in the rue family, mostly thorny trees or shrubs, which likely originate from China and India. The name citrus comes from the Ancient Greek kedrus or the Latin cedrus, and their cultivation in Southeast Asia began long before our era. They were known in Europe as early as antiquity, likely in connection with the campaigns of Alexander the Great. Further widespread expansion occurred during the Middle Ages, particularly thanks to the Moors. In the 16th century, the cultivation of oranges spread in Europe, and it was not until the 19th century that mandarins arrived in Europe from China.

They clear heat, quench thirst, generate body fluids, harmonise stomach function, and calm the foetus in the mother's womb. Do not consume in cases of stomach acidity, heartburn, or stomach ulcers. They activate calcium metabolism for bones and teeth. They stop bleeding gums; it is possible to rub them with lemon juice.

It has a sour taste and a cool to cold nature.