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alumroot

American  
[al-uhm-root, -root] / ˈæl əmˌrut, -ˌrʊt /

noun

  1. any of several North American plants belonging to the genus Heuchera, of the saxifrage family, especially H. americana, having mottled foliage and greenish-white flowers.

  2. the root of any of these plants, used as an astringent.


alumroot British  
/ ˈæləmˌruːt /

noun

  1. any of several North American plants of the saxifragaceous genus Heuchera, having small white, reddish, or green bell-shaped flowers and astringent roots

  2. the root of such a plant

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of alumroot

An Americanism dating back to 1805–15; alum 1 + root 1