Opuntia is a genus in the cactus family, Cactaceae.

The most common culinary species is the Indian fig opuntia (O. ficus-indica). Most culinary uses of the term "prickly pear" refer to this species. Prickly pears are also known as tuna (fruit) or nopal (paddle, plural nopales) from the Nahuatl word nōpalli for the pads, or nostle, from the Nahuatl word nōchtli for the fruit; or paddle cactus.

The genus is named for the Ancient Greek city of Opus, where, according to Theophrastus, an edible plant grew which could be propagated by rooting its leaves.