unfathomable

adjective

un·​fath·​om·​able ˌən-ˈfa-t͟hə-mə-bəl How to pronounce unfathomable (audio)
: not capable of being fathomed:
b
: impossible to comprehend
unfathomably adverb

Examples of unfathomable in a Sentence

His behavior is completely unfathomable. the unfathomable reaches of space
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Just as Natalia was starting her journalism career, the executives who controlled the industry were working to reinvent how daily newspapers operated — at the expense of an almost unfathomable number of journalists. Megan Greenwell, Rolling Stone, 5 June 2025 The concept is wild, but not completely unfathomable. Brian Mazique, Forbes.com, 31 May 2025 The unfathomable loss followed a two-year fertility journey that included in vitro fertilization, or IVF. Adrianna Rodriguez, USA Today, 25 Apr. 2025 Besting five runs would’ve been unfathomable for Toronto last week. Mitch Bannon, New York Times, 31 May 2025 See All Example Sentences for unfathomable

Word History

First Known Use

1640, in the meaning defined above

Time Traveler
The first known use of unfathomable was in 1640

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Cite this Entry

“Unfathomable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unfathomable. Accessed 25 Jun. 2025.

Kids Definition

unfathomable

adjective
un·​fath·​om·​able ˌən-ˈfat͟h-ə-mə-bəl How to pronounce unfathomable (audio)
: not capable of being fathomed:
b
: impossible to understand

More from Merriam-Webster on unfathomable

Last Updated: - Updated example sentences
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