Definition of track:
(n) :
a mark left by something that has passed along; as, the track, or wake, of a ship; the track of a meteor; the track of a sled or a wheel; a mark or impression left by the foot, either of man or beast; trace; vestige; footprint
(v) :
to
observe the (measured) state of an object over time; to
monitor someone's or something's movement