Un-dō', v. t.
[imp. UNDID; p. p. UNDONE; p. pr. & vb. n. UNDOING.]
Sense 1. To reverse, as what has been done; to annul; to bring to naught.
To-morrow, ere the setting sun, She’d all undo what she had done. Swift.
Sense 2. To loose; to open; to take to pieces; to unravel; to unfasten; to untie; as, to undo a knot.
She took the spindle, and, undoing the thread, gradually measured it. W. Scott.
Sense 3. To bring to poverty; to impoverish; to ruin, as in reputation, morals, or the like; as, many are undone by unavoidable losses, but more undo themselves by vices and dissipation, or by indolence.
Equivocation will undo her. Shak.