A division of an order; a group of genera of a little lower rank than an order and of greater importance than a tribe or family; as, cichoraceous plants form a suborder of Compositæ. [1913 Webster]

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OXFORD DICTIONARY

suborder, n. a taxonomic category between an order and a family.

Derivative

subordinal adj.

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THESAURUS

suborder

biotype, blood, bracket, branch, caste, category, clan, class, division, estate, family, genotype, genus, grade, group, grouping, head, heading, kin, kingdom, label, level, order, phylum, pigeonhole, position, predicament, race, rank, rating, rubric, section, sept, series, set, species, station, status, strain, stratum, subclass, subdivision, subfamily, subgenus, subgroup, subkingdom, subspecies, subtribe, superclass, superfamily, superorder, superspecies, title, tribe, variety

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