Voice-over (also voiceover) "[r]efers to a production technique where a disembodied voice is broadcast live or prerecorded in radio, television, film, theater and/or pre-sentation. The voiceover may be spoken by someone who also appears on- screen in other segments or it may be performed by a specialist voice actor." (Multilingual)

Voice-over can be used to add audio content in any language to video or film.

A related term is voice overlay.

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