Definition of pteridosperm in English:

pteridosperm

Syllabification: pte·rid·o·sperm
Pronunciation: /təˈridəˌspərm, ˈteridə-
 
/

noun

  • An extinct plant that is intermediate between the ferns and seed-bearing plants, dying out in the Triassic period. Also called seed fern.
    • Formerly placed in their own taxon (class Pteridospermeae), but now included with the gymnosperms
    More example sentences
    • The idea that cycads stem from Carboniferous so-called pteridosperms (‘seed ferns’ or seed plants with fern-like foliage) has long been popular with paleobotanists.
    • The Pteridopsida were present, bearing spores on their leaves as they do today, but there were also fernlike seed-bearing ferns, the pteridosperms.
    • The first seeds evolved in a group of vascular plants sometimes called the pteridosperms, or ‘seed ferns.’

Origin

early 20th century: from modern Latin pteridospermeae, from Greek pteris, pterid- 'fern'.

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