Shove

You can use the Shove maneuver to push a creature away. If you are able to make multiple attacks with the Attack action, this maneuver replaces one of them.

The target must be within your reach and be no more than one size category larger than you. The target makes a Strength saving throw against your maneuver DC. On a failure, you deal basic melee damage and push the target a number of feet away from you equal to 5 + 5 for every 5 points it failed its saving throw by. You can move the creature in any direction away from you (to the side, forward, or diagonally away).

A creature that is shoved off of a precipice is propelled off of whatever it is standing on—it does not receive any saving throw or ability check to grab onto something to avoid falling down below.