[1] : WordNet (r) 2.0

tone down
     v 1: deaden a sound or noise, especially by wrapping syn: muffle,
           mute, dull, damp, dampen
     2: make less strong or intense; soften; "tone down that
        aggressive letter"; "the author finally tamed some of his
        potentially offensive statements" syn: moderate, tame
see also:
muffle mute dull damp dampen moderate 
tame 

[2] : Moby Thesaurus II by Grady Ward, 1.0

102 moby thesaurus words for "tone down":
   abate, achromatize, allay, alleviate, assuage, atone, attemper,
   attune, baffle, bank the fire, blanch, bleach, blunt, chasten,
   chord, constrain, control, cushion, damp, dampen, de-emphasize,
   deaden, deafen, decolor, decolorize, dim, diminish, discolor,
   downplay, drain, drain of color, dull, ease, etiolate, extenuate,
   fade, fluff, fume, gentle, keep within bounds, knead, laxate, lay,
   lenify, lessen, lighten, limber, limber up, loosen, mash, massage,
   mat, mellow, milden, mitigate, moderate, modulate, mollify, muffle,
   mute, obtund, pale, palliate, peroxide, play down, plump, pulp,
   put in tune, reduce, reduce the temperature, relax, restrain,
   shake up, slacken, slow down, smash, smother, sober, sober down,
   soft-pedal, soften, soften up, squash, stifle, stop, string,
   subdue, supple, suppress, tame, tarnish, temper, tenderize,
   tone up, tune, tune down, tune up, underplay, voice, wash out,
   weaken, whiten

Break Down >> B Words
Break Down, definition of term: Break Down
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Bring Down >> B Words
Bring Down, definition of term: Bring Down
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Bow Down >> B Words
Bow Down, definition of term: Bow Down
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Boil Down >> B Words
Boil Down, definition of term: Boil Down
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Belt Down >> B Words
Belt Down, definition of term: Belt Down
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Back Down >> B Words
Back Down, definition of term: Back Down
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