枳，又称枸橘、枳壳、臭橘，属于芸香科枳属植物。

枳味苦，可作中药，中国《晏子春秋》中有“南橘北枳”的寓言，晏婴以此故事来说明环境的作用。但事实上，橘、枳为不同属的植物。

灌木或小乔木，有粗刺；复叶，小叶3片，有透明腺点，总叶柄具有翅；春末开白色花；球形小果实，成熟时为暗黄色，密被柔毛；果肉少味酸，不宜食用。

The trifoliate orange, Citrus trifoliata or Poncirus trifoliata, is a member of the family Rutaceae in the Citrus genus. Whether the species should be considered to belong to its own genus, Poncirus or included in the genus Citrus is debated. The species is unusual in Citrus for having deciduous, compound leaves and pubescent (downy) fruit.