To remove or invalidate by or as if by running a line through or wiping clean
To free from ties or fasteners
To become or cause to become open
To cause the complete ruin or wreckage of
To lessen or deplete the nerve, energy, or strength of
To lure or persuade into a sexual relationship or a sexual act
To bring to ruin
It was too late to undo what he had done.
Maybe he could undo what he'd done.
We will do, completely do, and undo these scoundrels.
She looked him in the eye, silhouetted in the glow from beneath the door, the only light in the nearly dark room, and began to undo his belt.
I can't undo what I did, but I will promise you that it will never happen again.