The surname Traill (also Trail, Traille, Traillie, Traily, etc.) Is derived from Norse to at least Norman via France (is not of French 'origin', 'origin' is the wrong word to use here, the first written records of it come from France via Normandy, its origin is Norse via Normandy at least), it does also seem to have some relation to words from the northern UK, pointing again to were it is derived from. It became "Traill" in Scotland (show any 'modern' non Scottish spread) and thence spread around the world.