Synonyms for Organization (same or very similar meaning)
WordNet sense 1 (the persons (or committees or departments etc.) who make up a body for the purpose of administering something):
administration, brass, establishment, governance, organisation, governing bodyWordNet sense 2 (an organized structure for arranging or classifying):
arrangement, systemWordNet sense 3 (the act of forming something):
constitution, formationFrom the ODE community, based on WordNetadd/edit