memberships

faithfuls, folds

collectives, communes, communities, cooperatives

alliances, blocs, camps, coalitions, partnerships

bodies, cadres, groups

circles, clans, cliques, coteries, juntas, juntos, klatches (also klatsches), lots, sets

crews, outfits, parties, squads, teams

branches, chapters, locals

sisterhoods, sororities

cabals, camarillas, camorras, confederacies, conspiracies

bands, gangs, rings

cartels, combines, syndicates

associations, boards, brotherhoods, chambers, clubs, colleges, congresses, consortia (also consortiums), councils, fellowships, fraternities, guilds (also gilds), institutes, institutions, leagues, orders, organizations, societies, sodalities

counts

classes, rosters

enrollments (also enrolments), registries

affiliations, alliances, associations, collaborations, confederations, connections, cooperations, hookups, liaisons, linkups, partnerships, relations, relationships, tie-ups, unions

businesses, dealings, interactions

exchanges, interconnections, interrelations, mutualisms, reciprocities, symbioses

incorporations, integrations, mergers, unifications

affinities, attachments, intimacies, rapports, sympathies

kinships, solidarities, unities

colleagueships, companies, companionships, fellowships

beds, cahoots, leagues