'Opuntia', commonly called prickly pear, is a genus in the cactus family, 'Cactaceae'. Prickly pears are also known as tuna (fruit), 'sabra', '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 and could be propagated by rooting its leaves. The most common culinary species is the Indian fig opuntia (O. ficus-indica).

O. ficus-indica is a large, trunk-forming, segmented cactus that may grow to 5–7 m (16–23 ft) with a crown of possibly 3 m (9.8 ft) in diameter and a trunk diameter of 1 m (3.3 ft).

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