lipsynch

/L IH1 P S IH1 NG K/
noun
  1. 1

    The synchronization of prerecorded audio signals and movement of the lips such that there is no lack of simultaneity between them.

verb
  1. 1

    To move lips in synchronization with sounds (generally recorded) so it appears they are the source of the sounds.

    โ€œShe lip-synced to her own recording during the show because of her laryngitis.โ€

Source: https://en.wiktionary.org/wiki/lip%20sync, https://en.wiktionary.org/wiki/lip-sync, https://en.wiktionary.org/wiki/lipsynch