antinoise

(ănˌtē-noizˈ, ănˌtī-)

adjective
  1. Designed to reduce environmental noise, as in a community: an antinoise ordinance.
  2. Capable of neutralizing the sound of another noise.
noun
A technique for neutralizing unwanted sound, in which a second sound wave, identical to but out of phase with the unwanted sound, is used to cancel the unwanted sound.
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