old-man's beard

noun

ˈōl(d)-ˈmanz- 

1

: any of several clematises (especially Clematis vitalba) having plumose styles

2

: a greenish-gray pendulous lichen (Usnea barbata) growing on trees

Examples of old-man's beard in a Sentence

Recent Examples on the Web

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

First Known Use

1731, in the meaning defined at sense 1

Medical Definition

old-man's beard

noun

ˌōl(d)-ˌmanz- 

: a greenish gray pendulous lichen of the genus Usnea (U. barbata) that grows on trees and is a source of usnic acid