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Showing results for undo. Search instead for unso.
Definitions

undo

[uhn-doo] / ʌnˈdu /
VERB
open
Synonyms
STRONGEST
loosen unlock unravel
STRONG
disengage disentangle free loose release unbind unblock unbutton unfasten unloose unloosen untie unwrap
WEAK
unclose unfix unshut unstop
Antonyms
STRONG
button fasten
WEAK
close do up
VERB
nullify, invalidate
Synonyms
STRONGEST
abolish annul destroy mar negate offset overturn quash reverse ruin shatter spoil subvert undermine wipe out wreck
STRONG
abate abrogate annihilate break cancel cramp craze crimp decimate defeat demolish have impoverish injure neutralize outfox outmaneuver outsmart overreach overthrow raze skin smash stymie unsettle upset vitiate wrack
WEAK
bring down bring to naught make waves screw up unbuild
Antonyms
STRONGEST
aid allow assist build construct create grow help permit repair restore support uphold
STRONG
approve balance encourage establish fix mend revive save
WEAK
validate

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“I know one guy who had a $2 million balance, pushed the wrong button and mistakenly converted the whole thing when he wanted to convert a portion. You can’t undo it. Conversions are permanent.”

From Barron's • Mar. 21, 2026

Nothing will ever undo the original sin, and devoting your life to ruining someone else’s is a loss for both of you.

From Los Angeles Times • Mar. 19, 2026

"There's still time to undo the wrong and hopefully wiser counsels will prevail," Gavaskar added.

From BBC • Mar. 16, 2026

A single, highly public moral failure could undo everything.

From Salon • Feb. 25, 2026

I undo the safety pins while Fiona gets our backpacks.

From "The Running Dream" by Wendelin Van Draanen

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.