The act of modulating, or the state of being modulated; as, the modulation of the voice. [1913 Webster]
Sound modulated; melody. Thomson. [1913 Webster]
A change of key, whether transient, or until the music becomes established in the new key; a shifting of the tonality of a piece, so that the harmonies all center upon a new keynote or tonic; the art of transition out of the original key into one nearly related, and so on, it may be, by successive changes, into a key quite remote. There are also sudden and unprepared modulations. [1913 Webster]
The alteration of hte amplitude, intensity, frequency, or phase (of the carrier wave of a radio signal) at intervals, so as to represent information to be transmitted. [WordNet 1.5]

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THESAURUS

modulation

AM, FM, PM, abatement, about-face, accommodation, adaptation, adjustment, allayment, alleviation, alteration, amelioration, amplitude modulation, apostasy, arrangement, assuagement, betterment, blunting, break, calming, change, change of heart, changeableness, constructive change, continuity, conversion, damping, deadening, defection, degeneration, degenerative change, demulsion, deterioration, deviation, difference, diminution, discontinuity, divergence, diversification, diversion, diversity, double sideband, dulcification, dulling, easing, falling-off, fitting, flip-flop, gradual change, harmonization, hushing, improvement, inflection, instrumentation, intonation, intonation pattern, leniency, lessening, letdown, letup, lightening, loosening, lulling, melioration, mitigation, modification, mollification, orchestration, overthrow, pacification, palliation, phrasing, pitch, pitch accent, preparation, qualification, quietening, quieting, radical change, re-creation, realignment, redesign, reduction, reform, reformation, relaxation, remaking, remission, renewal, reshaping, resolution, restructuring, reversal, revival, revivification, revolution, setting, shift, side frequency, sideband, slackening, softening, solution, soothing, speech tune, subduement, sudden change, suprasegmental, suspension, switch, tempering, tone, tone painting, total change, tranquilization, transcription, transition, turn, turnabout, upheaval, variation, variety, violent change, worsening

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ROGET THESAURUS

modulation

Change

N change, alteration, mutation, permutation, variation, modification, modulation, inflexion, mood, qualification, innovation, metastasis, deviation, turn, evolution, revolution, diversion, break, transformation, transfiguration, metamorphosis, transmutation, deoxidization, transubstantiation, mutagenesis transanimation, transmigration, metempsychosis, avatar, alterative, conversion, revolution &c (sudden or radical change), inversion, displacement, transference, changeableness, tergiversation, changed, newfangled, changeable, transitional, modifiable, alterative, mutatis mutandis, Int, quantum mutatus!, a change came o'er the spirit of my dream, nous avons change tout cela, tempora mutantur nos et mutamur in illis, non sum qualis eram, casaque tourner, corpora lente augescent cito extinguuntur, in statu quo ante bellum, still ending and beginning still, vox audita perit littera scripta manet.

Concord

N concord, accord, harmony, symphony, homologue, agreement, sympathy, empathy, response, union, unison, unity, bonds of harmony, peace, unanimity, league, happy family, rapprochement, reunion, amity, alliance, entente cordiale, good understanding, conciliation, peacemaker, intercessor, mediator, concordant, congenial, agreeing, in accord, harmonious, united, cemented, banded together, allied, friendly, fraternal, conciliatory, at one with, of one mind, at peace, in still water, tranquil, with one voice, in concert with, hand in hand, on one's side, commune periculum concordiam parit, melody concord, melody, rhythm, measure, rhyme, pitch, timbre, intonation, tone, scale, gamut, diapason, diatonic chromatic scale, enharmonic scale, key, clef, chords, modulation, temperament, syncope, syncopation, preparation, suspension, resolution, staff, stave, line, space, brace, bar, rest, appoggiato, appoggiatura, acciaccatura, note, musical note, notes of a scale, sharp, flat, natural, high note, low note, interval, semitone, second, third, fourth, diatessaron, breve, semibreve, minim, crotchet, quaver, semiquaver, demisemiquaver, hemidemisemiquaver, sustained note, drone, burden, tonic, key note, leading note, fundamental note, supertonic, mediant, dominant, submediant, subdominant, octave, tetrachord, major key, minor key, major scale, minor scale, major mode, minor mode, passage, phrase, concord, harmony, emmeleia, unison, unisonance, chime, homophony, euphony, euphonism, tonality, consonance, consent, part, harmony, harmonics, thorough-bass, fundamental-bass, counterpoint, faburden, piece of music, composer, harmonist, contrapuntist (musician), harmonious, harmonical, in concord, in tune, in concert, unisonant, concentual, symphonizing, isotonic, homophonous, assonant, ariose, consonant, measured, rhythmical, diatonic, chromatic, enharmonic, melodious, musical, melic, tuneful, tunable, sweet, dulcet, canorous, mellow, mellifluous, soft, clear, clear as a bell, silvery, euphonious, euphonic, euphonical, symphonious, enchanting fine-toned, full-toned, silver-toned, harmoniously, in harmony, as one, the hidden soul of harmony.

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