1. (n.) Agreement; accordance; harmony\.

2. (n.) Concord; agreement.

3. (n.) An alphabetical verbal index showing the places in the text of a book where each principal word may be found, with its immediate context in each place.

4. (n.) A topical index or orderly analysis of the contents of a book.

acclamation accompaniment accord accordance affinity agape agreement agreement of all alliance amity assent association atlas attune attunement bipartisanship bonds of harmony brotherly love cahoots calendar caritas casebook catalog catalogue raisonne cement of friendship charity chime chiming chorus city directory classified catalog co-working coaction coadjuvancy coadministration coagency cochairmanship codirectorship coherence coincidence collaboration collaborativeness collectivism collectivity collusion combination combined effort commensalism common assent common consent common effort common enterprise communalism communion communism communitarianism community community of interests compatibility complicity concentus concert concerted action concomitance concord concourse concurrence confluence conformance conformation conformity congeniality congruence congruency congruity conjunction consensus consensus gentium consensus of opinion consensus omnium consent consentaneity consilience consistency consonance consonancy consort conspiracy cooperation cooperativeness correspondence cyclopedia diapason diatesseron dictionary catalog directory duet duumvirate ecumenicalism ecumenicism ecumenism empathy encyclopedia equivalence esprit esprit de corps euphony feeling of identity fellow feeling fellowship frictionlessness gazetteer general acclamation general agreement general consent general voice good vibes good vibrations happy family harmonics harmony heavy harmony homophony identity index intersection joining of forces joint effort joint operation junction kinship like-mindedness love mass action meeting of minds monochord monody morale mutual assistance mutual understanding mutualism mutuality octet one accord one voice oneness overlap parallelism parasitism peace phone book polyglot pooling pooling of resources pulling together quartet quintet rapport rapprochement reciprocity record book reference book same mind saprophytism self-consistency septet sextet sharing simultaneity single voice solidarity source book studbook symbiosis symmetry sympathy symphony sync synchronism synchronization synergism synergy tally team spirit teamwork telephone book telephone directory three-part harmony timing total agreement trio triumvirate troika tune unanimity unanimousness understanding uniformity union unison unisonance united action unity universal agreement work of reference