usnea

noun

: any of a genus (Usnea of the family Parmeliaceae) of widely distributed lichens (such as old-man's beard) that have a grayish or yellow pendulous freely branched thallus

Examples of usnea in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The usnea—also called old-man's beard—looked ethereal in the dappled afternoon sunlight. Hannah Wallace, Condé Nast Traveler, 6 Aug. 2021

Word History

Etymology

New Latin, from Arabic ushna moss

First Known Use

1597, in the meaning defined above

Time Traveler
The first known use of usnea was in 1597

Dictionary Entries Near usnea

Cite this Entry

“Usnea.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/usnea. Accessed 21 Dec. 2024.

Medical Definition

Usnea

noun
Us·​nea ˈəs-nē-ə How to pronounce Usnea (audio)
: a genus of widely distributed lichens (family Usneaceae) including old-man's beard from which usnic acid is obtained
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