Read the dictionary definition of UNDO. All definitions for this word.
1. remove the outer cover or wrapping of
1. Let's unwrap the gifts!
2. undo the parcel
2. cause to become loose
1. undo the shoelace
2. untie the knot
3. loosen the necktie
3. cancel, annul, or reverse an action or its effect
1. I wish I could undo my actions
4. deprive of certain characteristics
5. cause the ruin or downfall of
1. A single mistake undid the President and he had to resign