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.
In this context, Roz’s sudden maternal reflexes are unfathomable. Armond White, National Review, 26 Feb. 2025 Borneo introduced the world of Survivor to fans with the unfathomable presentation of 16 castaways roughing it on an island, forming alliances and blindsiding their way to $1 million. Skyler Trepel, People.com, 25 Feb. 2025 Create And Share Specific Messaging Beyond Privacy And Terms Artificial intelligence is progressing at a rate that's genuinely unfathomable to understand. Expert Panel®, Forbes, 25 Feb. 2025 There are no shortcuts to the unfathomable heights Crosby has climbed. Chris Johnston, The Athletic, 19 Feb. 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 13 Mar. 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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