old man's beard

old man's beard (countable and uncountable, plural old man's beards or old men's beards)

1. (countable) Chionanthus virginicus, a tree.
2. Clematis aristata, an Australian climbing plant.
3. Clematis vitalba, a climbing plant.
4. (uncountable) Tillandsia usneoides, a bromeliad; Spanish moss.
5. (uncountable) Usnea, a type of lichen.

   Synonyms: beard lichen, usnea

6. Used other than figuratively or idiomatically: see old,‎ man,‎ -'s,‎ beard.
   • 1865, W. H. Ainsworth, Auriol; or, the Elixir of Life., G. Routledge & Sons, →OCLC, page 3:

     The old man's beard and hair were as white as snow—the former descending almost to his girdle; so were the thick overhanging brows that shaded his still piercing eyes.

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  Chionanthus virginicus
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  Spanish moss
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  Clematis vitalba seeds
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  Usnea