Athyrium

noun

Athyr·​i·​um

əˈthirēəm

: a genus of ferns (family Polypodiaceae) differing from Asplenium (in which it is often included) in having curved or lunate sori compare lady fern

Word History

Etymology

New Latin, irregular from Greek athoros without sperm (from a- a- entry 2 + thoros semen) + New Latin -ium; akin to Middle Irish dairim I leap upon, Sanskrit dhārā stream

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