trail -- (a track or mark left by something that has passed; "there as a trail of blood"; "a tear left its trail on her cheek")
trail -- (a path or track roughly blazed through wild or hilly country)
lead, track, trail -- (evidence pointing to a possible solution; "the police are following a promising lead"; "the trail led straight to the perpetrator")
trail, shack -- (move, proceed, or walk draggingly or slowly; "John trailed behind his class mates"; "The Mercedes trailed behind the horse cart")
trail -- (hang down so as to drag along the ground; "The bride's veiled trailed along the ground")
trail, train -- (drag loosely along a surface; allow to sweep the ground; "The toddler was trailing his pants"; "She trained her long scarf behind her")