Adiantum
noun
Ad·i·an·tum
| \ ˌad-ē-ˈant-əm
\
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Medical Definition of Adiantum
: a genus of ferns (family Polypodiaceae) with delicate palmately branched fronds comprising the maidenhair ferns and including two North American forms (A. pedatum and the Venushair A. capillus-veneris) that have been used in the preparation of expectorants and demulcents