Meaning

• An operation that reverses a previous action.

  "How many undos does this program support?"

Meaning

• To reverse the effects of an action.

  "Fortunately, we can undo most of the damage to the system by the war."

• To unfasten.

  "Could you undo my buckle for me?"

• To impoverish or ruin, as in reputation; to cause the downfall of.