| any tropical American poppy of the genus Argemone, esp. A. mexicana (Mexican poppy), having prickly pods and leaves and yellow or white, poppylike flowers. |

| prickly poppy n. Any of various plants of the genus Argemone, chiefly of tropical America, having large yellow, lavender, or white flowers and prickly leaves, stems, and pods. |
prickly poppy
any of approximately 30 species of the genus Argemone, North American and West Indian plants (one species endemic to Hawaii) belonging to the poppy family (Papaveraceae). Most are annuals or perennials with spiny leaves, prickly fruits, and white, yellow, or orange sap. The three sepals end in hornlike spines. Some species have become naturalized in arid regions of South America, Asia, and Africa. Prickly poppies are cultivated as garden ornamentals but frequently become troublesome weeds when growing wild. They were an important source of drugs in pre-Columbian Mexico. Parts of the 30- to 90-centimetre (1- to 3-foot), bristly-stemmed plants are still used by herbalists to treat a number of ailments.
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