Definition. A band of single prints at the extreme high or low of the session profile, formed when price was rejected quickly. In auction theory it marks the end of a move in that direction.
How it works
When price reaches a level where the other side of the market decisively steps in, the move reverses quickly. A thin “tail” remains in the time profile.
Example
The session begins with a fast drop that is sharply rejected. The low of the day has a clear tail, and the rest of the session trades higher.
What to watch out for
A tail shows the auction in that direction ended for the session. It doesn't guarantee the level won't be tested again.
You'll find the full explanation with graphics, examples and exercises in the 🖥️ Order flow atlas space, and its use in the live market in the 🔴 Live Room. Both are available to Club members (in Polish).