Alethopteris

noun

Al·​e·​thop·​ter·​is

ˌa-lə-ˈthäp-tə-rəs

: a genus of large fossil seed ferns represented by abundant remains in Carboniferous coal measures and having large bipinnate to tripinnate fronds with the thick pinnules being inserted on the rachis by a broad decurrent base

alethopteroid

¦a-lə-¦thäp-tə-ˌrȯid

adjective

Word History

Etymology

New Latin, from Greek alētho- (from alēthēs true) + New Latin -pteris

First Known Use

circa 1847, in the meaning defined above

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