: an order of herbaceous, arborescent, or occasionally climbing plants (class Filicineae) that comprise the true ferns, that are characterized by exstipulate fronds, leptosporangiate sporangial development, and small thin-walled sporangia which are usually borne in sori on the undersides of the fronds, and that have a characteristic ring of thick-walled cells which assists in dehiscence of the spores compare fern ally, pteridophyta
Word History
Etymology
New Latin, from Filic-, Filix + -ales
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