clapperboard

/ˈklæpərˌbɔrd/
noun
  1. A device used in filmmaking that has a hinged board and a clapper stick, used to mark the start of a scene and synchronize sound and picture.
    • Before each take, the clapperboard shows the scene and take numbers.
    • The director called 'Action!' and the assistant snapped the clapperboard shut.
    • The clapperboard's loud clap helps editors match the audio to the video.
Synonyms
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