noun Mi·cro·sper·mop·ter·is \-(ˌ)spərˈmäptərə̇s\

Definition of Microspermopteris

  1. :  a genus of Carboniferous seed ferns exhibiting features in common with the genera Lyginopteris and Heterangium and being of special interest because of the evidence it provides concerning the origin of seed plants from the Psilophytales

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Origin and Etymology of microspermopteris

New Latin, from micr- + sperm- + -pteris

Seen and Heard

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a rounded knoll or a ridge of ice

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