crank·shaft 
/ˈkræŋkˌʃæft, Brit ˈkræŋkˌʃɑ:ft/ noun
plural crank·shafts /ˈkræŋkˌʃæft, Brit ˈkræŋkˌʃɑ:ft/ noun [count] technical : a long metal piece that connects a vehicle's engine to the wheels and helps turn them — see picture at engine
