'Trail' is Latin for 'dragged marks' — from 'trahere' (to pull). A path revealed by what was dragged across it.
A path or track made across wild country (noun); to draw or drag along behind; to follow the trail of; to lag behind (verb).
From Old French trailler (to tow, to drag), from Vulgar Latin *tragulare (to drag a net, to trail), from Latin tragula (a drag-net, a javelin with a cord attached so it could be retrieved), from trahere (to drag, to pull), from PIE *tragh- (to drag along a surface). A trail was first a thing dragged — the dragnet trailed through the water, the javelin's cord trailed behind it. The path sense developed from the marks left by something dragged: the trail of a wounded animal, the trail of boots through snow, and eventually any path through