Adjust a receiver so as not to receive a signal, as in Let's tune out all this interference. [Early 1900s]
Dissociate oneself from one's surroundings; also, disregard, ignore. For example, The average reader, used to seeing lots of color images, tunes out when confronted with big blocks of text, or Some mothers are expert at tuning out the children's whining and quarreling. [1920s] For an antonym, see tune in.
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