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isoetes

noun
iso·​etes | \ īˈsōəˌtēz\

Definition of isoetes

1 capitalized : a large widely distributed genus (coextensive with the family Isoetaceae) of fern allies comprising the aquatic or marsh-growing quillworts that have a short buried lobed stem from which arises a tuft of quilt-shaped leaves bearing sporangia in their axils — see isoetales
2 plural isoetes : any plant of the genus Isoetes : quillwort sense 1

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History and Etymology for isoetes

New Latin, from Latin, houseleek, from Greek, from neuter of isoetēs equal in years, from is- + etos year

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