Sanguinaria canadensis (bloodroot) is a perennial, herbaceous flowering plant native to eastern North America. It is the only species in the genus Sanguinaria, included in the family Papaveraceae, and most closely related to Eomecon of eastern Asia.

Sanguinaria canadensis is also known as bloodwort, redroot, red puccoon, and sometimes pauson. It has also been known as tetterwort, although that name is also used to refer to Chelidonium majus. Plants are variable in leaf and flower shape and have in the past been separated out as different subspecies due to these variable shapes. Currently most taxonomic treatments include these different forms in one highly variable species. In bloodroot, the juice is red and poisonous.