noun Al·e·thop·ter·is \ˌa-lə-ˈthäp-tə-rəs\

Definition of Alethopteris

  1. :  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


\¦a-lə-¦thäp-tə-ˌrȯid\ adjective

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Origin and Etymology of alethopteris

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

First Known Use: circa 1847

Seen and Heard

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a rounded knoll or a ridge of ice

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