n.
Clapper rail (Zool.),
n. [ F. clapier. ] A rabbit burrow. [ Obs. ] [ 1913 Webster ]
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 ]
v. t. [ Clap + claw. ]