prickly pear

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of various cacti of the genus Opuntia, having bristly, flattened or cylindrical joints, showy, usually yellow flowers, and ovoid, often prickly fruit.
2. n. The often edible fruit of such a cactus.

Century Dictionary and Cyclopedia

1. n. The fruit of cacti of the genus Opuntia, a pear-shaped or ovoid berry, in many cases juicy and edible, armed with prickles or nearly smooth.
2. n. Any plant of this genus, primarily O. vulgaris (or O. Rafinesquii, which is not always distinguished from it). See Opuntia. These are native in barren ground on the eastern coast of the United States, the latter also in the upper Mississippi valley, the most northern species. With other members of the genus, they bear edible berries or pears. Some species support the cochineal-insect. (See cochineal.) Various species are available as uninflammable hedge-plants. O. Tuna, O. vulgaris, O. Ficus-Indica, and others are cultivated and more or less naturalized around the Mediterranean, etc., and their fruit is largely gathered for the market. Also called Indian fig.

Wiktionary

1. n. Any of various spiny cacti of the genus Opuntia, or the fruit, often edible, of such a plant.

GNU Webster's 1913

1. adj. (Bot.) a name given to several plants of the cactaceous genus Opuntia, American plants consisting of fleshy, leafless, usually flattened, and often prickly joints inserted upon each other. The sessile flowers have many petals and numerous stamens. The edible fruit is a large pear-shaped berry containing many flattish seeds. The common species of the Northern Atlantic States is Opuntia vulgaris. In the South and West are many others, and in tropical America more than a hundred more. Opuntia vulgaris, Opuntia Ficus-Indica, and Opuntia Tuna are abundantly introduced in the Mediterranean region, and Opuntia Dillenii has become common in India.

WordNet 3.0

1. n. cacti having spiny flat joints and oval fruit that is edible in some species; often used as food for stock
2. n. round or pear-shaped spiny fruit of any of various prickly pear cacti