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sidetone

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Fromside +‎tone.

sidetone (countable anduncountable,pluralsidetones)

1. The effect of sound that is picked up by thetelephone'smouthpiece and introduced (at low level) into theearpiece of the samehandset, acting asfeedback; or a similar effect in radiotelegraphy, public-address systems, etc.

• antisidetone

• side note,sidenote

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• en:Telephony

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