clapperboard

美 ['klæp?r.b?rd]

英 ['klæp?(r).b??(r)d]

复数：clapperboards

英英

n.	1. a pair of hinged boards filmed at the start of each take in a movie and clapped together to help to synchronize the soundtrack with the movie 2. a board consisting of two parts that are hit together before making part of a film, to make sure that the sound and picture happen at the same time