- to reverse the doing of; cause to be as if never done: Murder once done can never be undone.
- to do away with; erase; efface: to undo the havoc done by the storm.
- to bring to ruin or disaster; destroy: In the end his lies undid him.
- to unfasten by releasing: to undo a gate; to undo a button.
- to untie or loose (a knot, rope, etc.).
- to open (a package, wrapping, etc.).
- to explain; interpret.
- to untie, unwrap, or open or become untied, unwrapped, etc
- to reverse the effects of
- to cause the downfall of
- to explain or solve