From Traderpedia

Trading Range is a specifically defined term used by Joe Ross in his Law of Charts. Trading range is also a more general term used to describe consolidation.

A Trading Range is similar to a ledge, but must consist of more than ten price bars. The bars between ten and twenty are of little consequence. Usually, between bars 20 and 30, i.e., bars 21-29, there will be a breakout to the high or low of the Trading Range established by those bars prior to the breakout.