maidenhair

noun

maid·​en·​hair ˈmād-ᵊn-ˌha(ə)r, -ˌhe(ə)r 

: any of the genus Adiantum of ferns including two North American forms (A. pedatum and the Venus hair fern, A. capillus-veneris) that have been used in the preparation of expectorants and demulcents

called also maidenhair fern