| 释义 |
Definition of medullosan in English: medullosanadjective ˌmɛdəˈləʊsn Botany Of, relating to, or belonging to the group of extinct seed-bearing ferns (pteridosperms) including the genus Medullosa, known from Carboniferous and Permian fossils, whose stems have large, widely-spaced petioles and branched vascular cylinders.
noun ˌmɛdəˈləʊsn Botany A seed-bearing fern of the extinct genus Medullosa or the group to which it belongs.
Origin Early 20th century; earliest use found in Philosophical Transactions of the Royal Society of London. From Medullosa + -an. Definition of medullosan in US English: medullosanadjectiveˌmɛdəˈləʊsn Botany Of, relating to, or belonging to the group of extinct seed-bearing ferns (pteridosperms) including the genus Medullosa, known from Carboniferous and Permian fossils, whose stems have large, widely-spaced petioles and branched vascular cylinders.
nounˌmɛdəˈləʊsn Botany A seed-bearing fern of the extinct genus Medullosa or the group to which it belongs.
Origin Early 20th century; earliest use found in Philosophical Transactions of the Royal Society of London. From Medullosa + -an. |