Nachtmusik, absolute music, accidental, adaptation, adventitious, adventurous, air varie, aleatoric, aleatory music, amorphous, arrangement, blobby, blurred, blurry, broad, casual, causeless, chamber music, chamber orchestra, chance, chancy, chaotic, circumstantial, composition, conditional, confused, contingent, descant, destinal, dicey, disordered, electronic music, etude, exercise, fatal, fatidic, fluky, foggy, fortuitous, full of risk, fuzzy, general, harmonization, hazardous, hazy, hit-or-miss, iffy, ill-defined, imprecise, inaccurate, inchoate, incidental, incidental music, incoherent, indecisive, indefinable, indefinite, indeterminable, indeterminate, indistinct, inessential, inexact, instrumental music, invention, lax, loose, nocturne, nonessential, nonspecific, obscure, occasional, opus, orchestration, orderless, piece, production, program music, provisional, random, ricercar, riskful, risky, score, shadowed forth, shadowy, shapeless, sonata, sonatina, speculative, stochastic, string orchestra, string quartet, study, sweeping, theme and variations, trio, uncaused, unclear, undefined, undestined, undetermined, unessential, unexpected, unforeseeable, unforeseen, unlooked-for, unplain, unpredictable, unspecified, vague, variation, veiled, venturesome, venturous, wildcat, work

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