Thesaurus.com
Dictionary.com
Definitions

impossible

[im-pos-uh-buhl] / ɪmˈpɒs ə bəl /
ADJECTIVE
beyond the bounds of possibility
Synonyms
STRONGEST
absurd futile hopeless impassable impractical inaccessible inconceivable insurmountable preposterous unattainable unimaginable unreasonable unthinkable unworkable useless
STRONG
visionary
WEAK
beyond contrary to reason cureless hardly possible hundred-to-one impervious impracticable inexecutable infeasible irrealizable irreparable no-go no-win not a prayer out of the question too much unachievable uncorrectable unfeasible unobtainable unrecoverable way-out
Antonyms
STRONGEST
believable conceivable hopeful imaginable logical practical reasonable sensible
WEAK
achievable obtainable possible
ADJECTIVE
intolerable, ungovernable
Synonyms
STRONGEST
absurd hopeless ludicrous outrageous preposterous unacceptable unreasonable
STRONG
offensive undesirable
WEAK
egregious improper incongruous objectionable unanswerable unsuitable
Antonyms
STRONGEST
acceptable
STRONG
pleasing
WEAK
achievable believable governable manageable tenable tolerable

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.

More than 90% of pancreatic tumors carry a mutation called RAS, which accelerates tumor growth and historically has been nearly impossible to treat with drugs.

From The Wall Street Journal • Apr. 21, 2026

After 843 impossible days, the final deceased hostage was returned to his family for proper burial.

From The Wall Street Journal • Apr. 21, 2026

Being accused of attempting the impossible is not unusual for the scientists and engineers working on nuclear fusion projects around the world.

From BBC • Apr. 20, 2026

In 1988, for a walk-off home run by the hobbled Kirk Gibson in the World Series: “In a year that has been so improbable, the impossible has happened!”

From Los Angeles Times • Apr. 19, 2026

And most of all, he understood that impossible was to Olka what opportunity was to him.

From "Not Nothing" by Gayle Forman

Vocabulary lists containing impossible

List 1

Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!

myPerspectives 7.3

Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!

im-

Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!