Athyr·​i·​um | \ əˈthirēəm\

Definition of Athyrium

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

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History and Etymology for Athyrium

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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a secret plot to overthrow a government

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