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Past tense of undo.


the past tense of undo



v.t. -did, -done, -do•ing.
1. to reverse the doing of.
2. to repair or erase: to undo the damage.
3. to bring to ruin; destroy.
4. to unfasten or unlatch.
5. to untie.
[before 900]
un•do′a•ble, adj.


(anˈduː) past tense unˈdid (-ˈdid) : past participle unˈdone (-ˈdan) verb
1. to unfasten or untie. Could you undo the knot in this string?
2. to reverse, or destroy, the effect of. The evil that he did can never be undone.
unˈdoing noun
(the cause of) ruin or disaster. Gambling was his undoing.
unˈdone (-ˈdan) adjective
(of work, a task etc) not done, or not finished. I don't like going to bed leaving jobs/work undone.
References in classic literature ?
Two or three times, and more, Hepzibah repeated his name, without result; till, thinking her brother's sleep unwontedly profound, she undid the door, and entering, found the chamber vacant.
Attiring himself with as much care as if it had been for public worship, and precisely in the same manner, he stole softly down the staircase, undid the door, and issued forth.
It took no inconsiderable perseverance to arouse the inmates; but at last the respectable proprietor appeared, and undid the door.
Then I undid the mat, and he looked on the child, and laughed aloud.
Then the Prince, taking a bunch of copper keys from his pocket, undid the great double locks.
Reuben, a dark-brow'd and black-bearded Israelite, obeyed her summons, with a torch in his hand; undid the outward door of the house, and conducting Gurth across a paved court, let him out through a wicket in the entrance-gate, which he closed behind him with such bolts and chains as would well have become that of a prison.
However, he undid the chains by the help of magic, and took care of the Prince until he recovered and became strong enough to travel.
Tod turned his back towards the bed, and undid the window.
It is true that, in order to see if it was strong and fit to stand a cut, he drew his sword and gave it a couple of slashes, the first of which undid in an instant what had taken him a week to do.