unthinkable

adjective

un·​think·​able ˌən-ˈthiŋ-kə-bəl 

1

: not capable of being grasped by the mind

2

: being contrary to what is reasonable, desirable, or probable : being out of the question

unthinkability

ˌən-ˌthiŋ-kə-ˈbi-lə-tē 

noun

unthinkably

ˌən-ˈthiŋ-kə-blē 

adverb

Synonyms

• fantastic
• fantastical
• implausible
• inconceivable
• incredible
• incredulous
• unbelievable
• uncompelling
• unconceivable
• unconvincing
• unimaginable

Examples of unthinkable in a Sentence

to most people it seemed unthinkable that such a gentle man could be guilty of such awful crimes

Recent Examples on the Web

This kind of candor about mental health would have been unthinkable a decade ago. —Brendan Keegan, Rolling Stone, 1 Nov. 2024

Not long ago, such activist drama at Southwest would have been unthinkable. —Lila MacLellan, Fortune, 26 Oct. 2024

For example, over a quarter of a billion people watching a show like Wednesday would have been unthinkable before the rise of streaming. —Callum Booth, Forbes, 14 Oct. 2024

Their bond begins to fray, and betrayal—once utterly unthinkable—now becomes all too possible. —Andreas Wiseman, Deadline, 1 Nov. 2024

Word History

First Known Use

15th century, in the meaning defined at sense 1

Phrases Containing unthinkable

• the unthinkable

Kids Definition

unthinkable

adjective

un·​think·​able ˌən-ˈthiŋ-kə-bəl 

ˈən-

: not to be thought of or considered as possible

unthinkable cruelty