bipartisanship clover coaction coadjuvancy coadministration coagency cochairmanship codirectorship collaboration collaborativeness collectivism collusion commensalism common effort common enterprise communalism communism communitarianism community complicity concert concord concordance concurrence cooperation cooperativeness deuce-ace duet duumvirate ecumenicalism ecumenicism ecumenism esprit esprit de corps fellow feeling fellowship harmony joining of forces joint effort joint operation leash mass action morale mutual assistance mutualism mutuality octet pooling pooling of resources pulling together quartet quintet reciprocity septet set of three sextet shamrock solidarity symbiosis synergism synergy team spirit teamwork tercet ternary ternion terzetto three threesome tierce trefoil trey triad trialogue triangle tricorn trident triennium trihedron trilogy trimester trine trinity trinomial trio triphthong triple triple crown triple threat triplet triplopy tripod triptych trireme triseme triskelion trisul triumvirate triune triunity trivet united action