un|do

un|do «uhn DOO», transitive verb, -did, -done, -do|ing.

1. to unfasten and open; unloose and remove the wrapping of: »

“Please undo the package,” she said.

2. to untie: »

to undo a knot. I undid the strin

3. to do away with; cause to be as if never done; cancel or reverse; rescind: »

What's done, cannot be undone (Shakespeare).

SYNONYM(S): annul.

4. to bring to ruin; spoil; destroy: »

The workmen mended the road, but a heavy storm undid their work. Curse on his virtues! they've undone his country (Joseph Addison).

5. to unlock the mystery of; explain; solve.

╂[Old English undōn < un- un-² + dōn to do]

–un|do´er, noun.