clapperboard

Plural: clapperboards

Noun

• photographic equipment used to synchronize sound and motion picture; boards held in front of a movie camera are banged together
• A device used in film production, having hinged boards that are brought together with a clap, used at the start of each take of a motion picture or other video production to be able to synchronize picture and sound during editing.

Verb

• To use a clapperboard, especially to clap it to start a film take.

Synonyms

board, clapboard, clapstick, marker, slate, slate board, sticks, sync slate