(n.) A composition for eight parts, usually for eight solo instruments or voices.

Octateuch Spenserian stanza antistrophe beta particle bipartisanship book burden canto cathode particle chorus 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 couplet distich duet duettino duo duumvirate ecumenicalism ecumenicism ecumenism eight eighter from Decatur electron electron affinity electron cloud electron pair electron shells electron spin electron transfer electron-positron pair energy level ensemble music ensemble singing envoi epode esprit esprit de corps excited state extranuclear electrons fellow feeling fellowship ground state harmony heptastich hexastich joining of forces joint effort joint operation line lone pair mass action measure monostich morale mutual assistance mutualism mutuality negatron octad octagon octahedron octameter octastich octastyle octave octavo octonary octosyllable ogdoad orbital electron ottava rima part music part singing part song pentastich photoelectron polyphonic music pooling pooling of resources pulling together quartet quatrain quintet reciprocity recoil electron refrain rhyme royal secondary electron septet septuor sestet sextet shared pair solidarity stanza stave strain strophe subvalent electrons surface-bound electron syllable symbiosis synergism synergy team spirit teamwork tercet terza rima terzet terzetto tetrastich thermion trio triplet tristich triumvirate troika united action utas valence electrons valence shell verse wandering electron