| any of several large, cylindrical, ribbed, spiny cacti of the genera Echinocactus and Ferocactus. |
| barrel cactus n. Any of several cacti, especially in the genera Ferocactus and Echinocactus, having unbranched, globular to columnar, ribbed spiny stems. |
barrel cactus
name for a group of more or less barrel-shaped cacti, family Cactaceae, native to North and South America. It is most often used for two large-stemmed North American genera, Ferocactus and Echinocactus. Small barrel cacti include the genera Sclerocactus, Neolloydia, and Thelocactus, and other barrel cacti are Astrophytum and some species of Thelocactus that were previously placed in Hamatocactus.
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