Definition of Aaron's beard in US English:

Aaron's beard

noun

  • a name given to various plants, especially the rose of Sharon (sense 2 of the noun)
    • ‘Aaron's beard does well in full sun to partial shade, and tolerates almost complete shade.’
    • ‘Plants such as winter creeper and Aaron's beard may become rangy and untidy.’
    • ‘I was considering growing Hypericum calycinum (Aaron's Beard) under/in front of my azaleas after reading about them in a book on gardening in the Mid-Atlantic.’

Origin

Early 19th century: alluding to Aaron, whose beard ‘went down to the skirts of his garments’ (Ps. 133:2), because of the prominent hairy stamens or the long runners which some of these plants put out.

Pronunciation

Aaron's beard

/ˌerənz ˈbird/