1.To reverse, as what has been done; to annul; to bring to naught. "What's done can not be undone." "To-morrow, ere the setting sun, She 'd all undo that she had done."
2.To loose; to open; to take to piece; to unfasten; to untie; hence, to unravel; to solve; as, to undo a knot; to undo a puzzling question; to undo a riddle. "Pray you, undo this button." "She took the spindle, and undoing the thread gradually, measured it."
3.To bring to poverty; to impoverish; to ruin, as in reputation, morals, hopes, or the like; as, many are undone by unavoidable losses, but more undo themselves by vices and dissipation, or by indolence. "That quaffing and drinking will undo you,"
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