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.
Think of it as Bannon on the one side, versus Newt Gingrich, anti-tax crusader Grover Norquist and others on the other — a debate that once seemed unfathomable for Republicans who have spent generations working to lower taxes and reduce the scope of the federal government. Lisa Mascaro, Los Angeles Times, 25 Apr. 2025 The overwhelming interest in last week’s classic car review was unfathomable. Marc D Grasso, Hartford Courant, 19 Apr. 2025 In a small van with one pup already, the thought of taking in a street dog seemed unfathomable. John W. Dean, MSNBC Newsweek, 7 Apr. 2025 These policies disregard merit and achievement and unleash unfathomable harms upon the lives, families, and careers of transgender servicemembers. Dan Perry, Newsweek, 19 Mar. 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 1 May. 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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