Thesaurus.com
Dictionary.com
Definitions

unstoppable

[uhn-stop-uh-buhl] / ʌnˈstɒp ə bəl /
ADJECTIVE
irrepressible
Synonyms
STRONGEST
boisterous buoyant ebullient exuberant rebellious uncontrollable unrestrained
WEAK
bubbling bubbly enthusiastic inextinguishable insuppressible rhapsodical unconstrained uncontainable unmanageable unquenchable unrestrainable unruly
Antonyms
STRONGEST
controllable restrained
WEAK
depressed despondent grave
ADJECTIVE
relentless
Synonyms
STRONGEST
determined dogged ferocious fierce harsh implacable inexorable rigorous ruthless single-minded uncompromising unforgiving unrelenting unyielding
WEAK
adamant bound bound and determined dead set on go for broke grim hang in hang-tough hard inflexible inhuman mortal obdurate pitiless remorseless rigid stiff stop-at-nothing strict stringent unappeasable unbending undeviating unflinching vindictive
Antonyms
STRONGEST
compassionate easy flexible gentle irresolute kind lenient merciful mild nice nonviolent peaceful remorseful sympathetic tame tender yielding
WEAK
ending intermittent stopping understanding
ADJECTIVE
relentless
Synonyms
STRONGEST
incessant nonstop persistent punishing sustained tenacious unflagging unrelenting unremitting
WEAK
pertinacious unabated unbroken unfaltering unrelieved
Antonyms
STRONGEST
intermittent relenting surrendering yielding
WEAK
ending kind merciful stopping sympathetic understanding

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.

Until Skenes and a combination of five relievers shut them down, the Dominicans had looked all but unstoppable.

From The Wall Street Journal • Mar. 16, 2026

Bailee Broward also made some outside shots, giving the Cardinals unstoppable inside-outside options.

From Los Angeles Times • Mar. 13, 2026

This year's Bafta Games Awards nominations have been released, and the unstoppable Clair Obscur: Expedition 33 is the front-runner once again.

From BBC • Mar. 12, 2026

With a dazzling array of unstoppable female characters, Taylor Sheridan’s ‘1923’ is the show every adult American Girl doll fan should be watching.

From Los Angeles Times • Mar. 1, 2026

Einstein quickly realized that with atomic bombs, Adolf Hitler would be absolutely unstoppable.

From "Bomb" by Steve Sheinkin

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