Word Study
clapperboard
CIDE DICTIONARY
clapperboard, n.
a device which synchronizes sound and picture while making a motion picture, consisting of boards held in front of a movie camera, which are are banged together. [WordNet 1.5]
OXFORD DICTIONARY
clapperboard, n. Cinematog. a device of hinged boards struck together to synchronize the starting of picture and sound machinery in filming.
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