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.
Future threats to Uruguayan waterfowl conservation notwithstanding, for our group of American bird hunters, another clear-cool afternoon proves ideal to visit the edge of a grove of eucalyptus, a favorite roost for nearly unfathomable numbers of doves. Chris Dorsey, Forbes.com, 30 June 2025 Here are the four teams that did the unfathomable and won on the road: Cavs over Warriors (2016): LeBron James had The Block, Kyrie Irving hit that go-ahead shot and Kevin Love had The Stop in a 93-89 win. Zach Harper, New York Times, 20 June 2025 Shaw should also include the majority of roughly 7,000 governmental bodies in Illinois; the state has unfathomable pension debt. Chicago Tribune, 13 June 2025 And here’s the kicker: Colorado’s overall record is an almost unfathomable 9-48, putting them on pace to go 26-136. Patrick Saunders, Denver Post, 30 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 18 Jul. 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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