pedrail
/ˈpɛdreɪl/noun
A type of tractor or traction engine designed for passing over obstacles and rough terrain.
- The wheels have circular rims bearing hinged, spring-loaded pads or feet at the end of the spokes; these feet successively make contact with the ground as the wheel turns. On each spoke there is also a roller adjacent to the foot, which bears against a cam inside the periphery of the wheel..
Origin
Early 20th century; earliest use found in The Daily Chronicle. From classical Latin ped- + rail.