Juggling

From TF2 Wiki

Juggling refers to the Soldier's ability to use the rocket launcher's splash damage to lift an opponent into the air (also called the 'bounce effect'). In effect, this does away with the opponent's ability to dodge and allows the Soldier to subsequently predict where they will land. It gives the Soldier the opportunity to score a direct hit, or even to shoot the opponent out of the air. More agile or powerful enemies may require several of these bounces to take out, hence the term juggling.

It is possible for the Demoman to juggle by using sticky bombs, but it is more difficult to execute than by using the Soldier's rocket launcher. In this case, it is oftentimes easier to kill the opponent more directly without juggling.

Juggling can be used to separate an Ubercharged Medic from his target by knocking the Medic out of range, so as to cut off the Ubercharge prematurely.