Chelidonium majus, commonly known as the greater celandine or tetterwort (in America, the latter refers to Sanguinaria canadensis), is the only species in the genus Chelidonium, family Papaveraceae. The lesser celandine is not closely related, but its family, the Ranunculaceae, is allied to the Papaveraceae (Order Ranunculales). The greater celandine is native to Europe and the Mediterranean basin. It is also widespread in North America, having been brought there by settlers as a herbal remedy for skin problems such as warts as early as 1672.
Greater celandine has an erect habit, and may reach 30 to 120 cm high. The leaves are deeply divided, 30-cm long, and crenate. The sap is bright opaque yellow. The flowers comprise four yellow petals, each about 1 cm long, with two sepals. The flowers appear from May to July. The seeds are small and black, and possess an elaiosome, which attracts ants to disperse the seeds (myrmecochory). A double-flowered variety, a naturally occurring mutation, also exists. It is considered an aggressive invasive plant in natural areas (both woods and fields). Control is mainly via pulling or spraying the plant before seed dispersal.