What does "undo" mean?

Undo: 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. Tennyson. Pray you, undo this button. Shak. She took the spindle, and undoing the thread gradually, measured it. Sir W. Scott.

Additional senses

  1. 2.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, Shak.

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