unimpeachable

American  

[uhn-im-pee-chuh-buhl] / ˌʌn ɪmˈpi tʃə bəl /

adjective

1. above suspicion; impossible to discredit; impeccable.

   unimpeachable motives.

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unimpeachable British  

/ ˌʌnɪmˈpiːtʃəbəl /

adjective

1. unquestionable as to honesty, truth, etc

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Other Word Forms

• unimpeachability noun
• unimpeachableness noun
• unimpeachably adverb

Etymology

Origin of unimpeachable

First recorded in 1775–85; un- ¹ + impeachable

Explanation

Unimpeachable describes someone or something that is totally, completely, without any doubt, innocent and good, like an unimpeachable role model who avoids bad influences and sketchy situations. Impeach means "to accuse, or charge with a crime." It is a verb usually reserved for when high-ranking officials like presidents do something wrong. So, when you add the prefix un- and the suffix -able, the result is an adjective that means "not able to be accused," in other words, beyond doubt or question. If you run for public office and your past is unimpeachable, your opponents will have nothing to use against you in their advertisements.

Example Sentences

Mr. Polito identifies Mr. Dylan’s myriad sources, the contents of the box, often from unimpeachable evidence: the songwriter’s own scribbles in the margins of his manuscripts.

From The Wall Street Journal • Feb. 6, 2026

But this is Harlan Coben and Reese Witherspoon we’re talking about here, two formidable talents whose track record for delivering smart entertainment is unimpeachable.

From Los Angeles Times • Oct. 6, 2025

So artists have had to create a kind of whisper network to withstand New York’s unimpeachable forward march, which the art market has, ironically, enabled.

From New York Times • Feb. 26, 2024

"The court of appeals decision was thoughtful and forceful and, I think, solid, and forgive the pun, but unimpeachable," Rosenberg said.

From Salon • Feb. 7, 2024

Morrison raised his eyebrows to indicate the unimpeachable logic of this statement.

From "Middlesex: A Novel" by Jeffrey Eugenides