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Definition of mammillaria

1 capitalized : a large genus of usually low-growing roundish or cylindrical cacti that often grow in clumps, have round, angular, or cone-shaped tubercles tipped with few to many straight or hooked spines, and usually small pink, red, yellow, or white flowers

Note: Cacti of the genus Mammillaria are found from the southwestern U.S. to South America and the West Indies, with most species native to Mexico. The key identifying characteristics of this genus are that the surface of the tubercle does not possess any grooves and that flowers arise from the base of the tubercle.

2 plural -s : any cactus of the genus Mammillaria

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History and Etymology for mammillaria

New Latin, from Latin mammilla + New Latin -aria

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Cite this Entry

“Mammillaria.” The Dictionary, Merriam-Webster Inc., Accessed 26 January 2020.

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