Anything that indicates future trends.
A stock or bond that is widely believed to be an indicator of the overall market's condition.
The leading sheep of a flock, having a bell hung round its neck.
A mechanical pencil.
One who paces.
In harness racing, a horse with a gait in which the front and back legs on one side take a step together alternating with the legs on the other side; as opposed to a trotter.
A pacemaker (one who sets the pace in a race).