(botany) Of or pertaining to the pteridosperms.

Of or pertaining to the ferns of the division Pteridophyta.

Any of various extinct gymnosperms, of the division Pteridospermatophyta, resembling ferns, but producing seeds instead of spores

plural of pteridosperm

(organic chemistry) A ketonic amide derivative of pteridine responsible for some of the colouring in nature. It is also a component of folic acid.

(organic chemistry) A bicyclic aromatic heterocycle consisting of fused pyrimidine and pyrazine rings

plural of pteridine

plural of pteranodon

A member of Pteranodon, a genus of large pterosaurs, the males of which had a bony crest on the back of the head.

wing