Resistance

Abjuration Cantrip (Artificer, Cleric, Druid)

Casting Time: Reaction, which you take in response to you or an ally within 10 feet of you failing a Saving Throw
Range: 10 feet
Components: V, S
Duration: Instantaneous

You channel magical protection to the creature who failed the Saving Throw. That creature can roll a d4 and add the number rolled to the save, potentially turning it into a success.

Source: Cleric and Revised Species