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old-man cactus

American  
[ohld-man] / ˈoʊldˌmæn /

noun

  1. a Mexican cactus, Cephalocereus senilis, having a columnar body from 30 to 40 feet (9 to 12 meters) high with thatchlike, long, white hairs on the top, and red flowers with white centers.

Etymology

Origin of old-man cactus

An Americanism dating back to 1895–1900

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.