offshoot

n. shoot growing from the main stem; branch, derivative

This article describes the game show Spin-Off. The article about a large group splitting to form a new group can be found at Spin-off.Spin-Off was a short-lived American game show from 1975 that was based on the dice game Yahtzee and starred Jim Lange, and was originally produced by Nick Nicholson and Roger Muir.
See more at Wikipedia.org...

A spin-off (or spinoff) is a new organization or entity formed by a split from a larger one, such as a television series based on a pre-existing one, or as a new company formed from a university research group or business incubator. In literature, especially in milieu based popular fictional book series like mysteries, westerns, fantasy, or science fiction the term sub-series is generally used instead of spin-off, but with essentially the same meaning.
See more at Wikipedia.org...

Noun
1. a natural consequence of development
(synonym) outgrowth, branch, offset
(hypernym) consequence, effect, outcome, result, event, issue, upshot

(n.)
That which shoots off or separates from a main stem, channel, family, race, etc.; as, the offshoots of a tree.
  

Synonyms and related words:
V, accession, accessory, accompaniment, addenda, addendum, additament, addition, additive, additory, additum, adjunct, adjuvant, affiliate, affiliation, annex, annexation, appanage, appendage, appendant, appurtenance, appurtenant, arm, attachment, augment, augmentation, bine, body, bough, branch, branch office, branchedness, branchiness, breakaway group, burgeon, by-product, camp, caucus, chapter, church, coda, communion, community, complement, concomitant, consequence, consequent, continuation, corollary, crotch, crutch, deadwood, delta, denomination, derivation, derivative, descendant, development, distillate, division, effect, ethnic group, event, eventuality, eventuation, extension, extrapolation, faction, fan, fellowship, filiation, fixture, flagellum, fork, frond, fruit, furcula, furculum, groin, group, hand, harvest, heir, imp, increase, increment, inguen, interest, interest group, issue, joint, kin, kindred, leg, legacy, limb, link, lobe, lobule, local, lodge, logical outcome, member, minority group, offset, offspring, order, organ, organization, outcome, outgrowth, party, pendant, persuasion, pinion, political party, post, precipitate, pressure group, product, prong, ramage, ramification, reinforcement, relation, relative, religious order, result, resultant, runner, sarment, schism, school, scion, sect, sectarism, segment, sequel, sequela, sequence, sequent, shoot, side, side effect, side issue, silent majority, slip, society, spear, spin-off, splinter, splinter group, spray, sprig, sprit, sprout, spur, stem, stolon, sucker, supplement, switch, tail, tailpiece, tendril, thallus, trident, twig, undergirding, upshot, variety, version, vocal minority, wing, wishbone