Momentum

Momentum, on a chart, refers to the rate at which price is changing rather than its level or its direction. A move that covers the same distance in fewer periods is described as having more momentum than one that takes longer, and most of the oscillators on a standard platform are some arrangement of that comparison: current price set against price a chosen number of periods earlier. Because it is a rate, momentum can fall while price still rises — the move continues but covers less ground per period — and the gap between the two is where much of the vocabulary around the word comes from. The number of periods being compared is a setting, so momentum is never a property of the instrument on its own; it is a property of the instrument and the lookback together. Change the lookback and the same stretch of chart can be described as gaining or as losing momentum, without a single price having changed.