soften somebody/something ↔ up phrasal verb ( see also ↑ soften )
1 . informal to be nice to someone before you ask them to do something, so that they will agree to help you:
She was just softening me up.
2 . to make an enemy weaker so that they are easier to attack:
Use artillery to soften up the enemy forces.
3 . to make something less hard or rough