Subgroup

n.

1.

(Biol.) A subdivision of a group, as of animals.

Noun	1.	subgroup - a distinct and often subordinate group within a group
	2.	subgroup - (mathematics) a subset (that is not empty) of a mathematical group

adjunct, blood, bracket, branch, caste, category, clan, class, component, contingent, cross section, detachment, detail, division, dole, estate, fraction, grade, group, grouping, head, heading, installment, item, kin, label, level, order, parcel, part, particular, percentage, pigeonhole, portion, position, predicament, quadrant, quarter, quota, race, random sample, rank, rating, remainder, rubric, sample, sampling, section, sector, segment, sept, set, share, station, status, strain, stratum, subdivision, suborder, subspecies, title