Definitions

inconceivable

[in-kuhn-see-vuh-buhl] / ˌɪn kənˈsi və bəl /

ADJECTIVE

beyond reason, belief

Synonyms

STRONGEST

extraordinary implausible impossible improbable incredible mind-boggling strange unbelievable unheard-of unimaginable unthinkable

WEAK

fantastic incogitable incomprehensible insupposable phony rare reachy staggering thin unconvincing unknowable unlikely unsubstantial weak won't fly won't wash

Antonyms

STRONGEST

believable common credible familiar likely normal plausible possible reasonable tenable usual

WEAK

conceivable fathomable imaginable

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.

“It seems inconceivable to me that we would voluntarily relinquish the leadership that has propelled our country, fueled the economy, made us healthier, and made us safer,” he said.

From Los Angeles Times • May 6, 2026

Two men broke a previously inconceivable barrier at the London Marathon on Sunday, both running 26.2 miles in under two hours and smashing the world record.

From The Wall Street Journal • Apr. 26, 2026

That’s what happens when you have a fastball that reaches 100 miles per hour, a disappearing splitter and an array of breaking balls with inconceivable movement.

From The Wall Street Journal • Apr. 10, 2026

"She will have seen just as much as Andrew. It's inconceivable that she didn't. She was so matey with Epstein."

From BBC • Mar. 20, 2026

Now… where were we in our inconceivable tale?

From "The Undead Fox of Deadwood Forest" by Aubrey Hartman

Vocabulary lists containing inconceivable

The Diary of Anne Frank

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Essential Academic Vocabulary for High School Students, List 2

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List 3

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