accompaniment accordance affiliation agreement alignment alliance amalgamation association co-working coaction coadunation coalescence coalition coincidence collaboration colleagueship collectivity collegialism collegiality collusion combination combined effort comradeship concert concerted action concomitance concordance concourse concurrence confederacy confederation confluence confraternity conjunction consilience consolidation conspiracy cooperation copartnership copartnery correspondence federation fellowship fraternalism fraternity fraternization freemasonry fusion hookup inclusion incorporation integration junction league merger parasitism partnership saprophytism simultaneity sodality sorority symbiosis synchronism synergy tie-in tie-up unification union united action