Meaning & use
undo
To reverse or cancel an action, or to unfasten something that was tied or done up.
See it in a sentence
Click this button to undo your last change in the document.
He carefully undid the knot with a few gentle tugs of the rope.
A note on using this word
Undo is irregular: past tense undid, past participle undone.
Words with a similar meaning
reverseunfasten
Choose a synonym to suit the sentence. Meanings can overlap without being identical.
Words with an opposite meaning
fastenconfirm
Make it your own
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