unimaginable

adjective

un·​imag·​in·​able

ˌən-ə-ˈmaj-nə-bəl, 

-ˈma-jə- 

: not imaginable or comprehensible

unimaginable horror

technology that was unimaginable only a few years ago

unimaginably

ˌən-ə-ˈmaj-nə-blē, 

-ˈma-jə 

adverb

Synonyms of unimaginable

• incredible
• incredulous
• unlikely
• impossible
• inconceivable
• unthinkable
• unbelievable

Examples of unimaginable in a Sentence

the unimaginable horrors of war

a disaster of almost unimaginable proportions

This technology would have been unimaginable five years ago.

Recent Examples on the Web

Built in Southern California, the Endeavour embodies the shuttle program’s technological ambition and diversity, while reminding visitors how cooperation can make the unimaginable possible. — Laura Zornosa, Los Angeles Times, 28 Oct. 2026

Lawmakers have begun rebuking Israel in ways that were once unimaginable. — Annie Karni, New York Times, 27 Oct. 2026

Despite our best intentions, the myth becomes a caricature of sorts…This has the effect of making them, essentially, unimaginable. — Literary Hub, 26 Oct. 2026

What happened in that classroom was unimaginable, and like so many in this community, my heart is broken for everyone affected by this tragedy. — Katu Staff, Baltimore Sun, 22 Oct. 2026

Word History

First Known Use

1611, in the meaning defined above

Rhymes for unimaginable

• imaginable