lip-sync

or lip·synch, lip·sync

[ lip-singk ]
/ ˈlɪpˌsɪŋk /
Movies, Television.
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verb (used with or without object)

to synchronize (recorded sound) with lip movements, as of an actor in a film.
to match lip movements with (recorded speech or singing): She did a clumsy job of lip-syncing her big song.

noun

the technical process by which this is done.
the simultaneous recording of voice and picture, especially the synchronization of lip movements with recorded sound.

Origin of lip-sync

First recorded in 1960–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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