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wall rue

American  

noun

  1. a small, delicate fern, Asplenium rutamuraria, having fan-shaped leaflets and growing on walls and cliffs.

wall rue British  

noun

  1. a delicate fern, Asplenium ruta-muraria, that grows in rocky crevices and walls in North America and Eurasia

"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 wall rue

First recorded in 1540–50

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.