clapboard UK /ˈklæpˌbɔːd/US /ˈklæpˌbɔɹd/noun 4verb 1forms 3 noun4 •A narrow board, usually thicker at one edge than the other, used as siding for houses and similar structures of frame construction.Its exterior is covered with clapboards stained dark brown. — 2007 •Such boards, arranged horizontally and overlapping with thick edge down, collectively, as siding.Bond turned to the window and watched the pretty clapboard houses slip by as they approached Trenton. He loved trains and he looked forward with excitement to the rest of the journey. — 1954 •A clapperboard; a device used in film production, having hinged boards that are brought together with a clap, used to synchronize picture and sound at the start of each take of a motion picture or other video production. •(UK, no longer used) An oak board of a size used for barrel staves. verb1 •To cover with clapboards. formsclapboarded · clapboarding · clapboards