un·​fath·​om·​able ˌən-ˈfa-t͟hə-mə-bəl How to pronounce unfathomable (audio)
: not capable of being fathomed:
: 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 Morgan Freeman, the series’ narrator, tells viewers early on that ninety-nine per cent of all species that have ever lived are now extinct—a fact whose contours are unfathomable. Rivka Galchen, The New Yorker, 6 Nov. 2023 The president also knows that countries need to be able to cooperate on challenges that were unfathomable not that long ago. Jake Sullivan, Foreign Affairs, 24 Oct. 2023 Idaho’s producers grow nearly one-third of all the potatoes in the U.S. a year — an unfathomable 11.2 billion pounds on more than 300,000 acres, earning the state its reputation as a total spud. Rachel Chang, Travel + Leisure, 22 Sep. 2023 Then the writers had to solve the challenge of making unfathomable scales of time and change feel intelligible, at least a bit. Rivka Galchen, The New Yorker, 6 Nov. 2023 The program has already returned riches from those almost unfathomable depths. Phil Plait, Scientific American, 3 Nov. 2023 Earlier Friday, law enforcement authorities had deployed divers to search the Androscoggin River and combed through nearby forests as the search for the gunman stretched into a third day and the city of Lewiston began to reckon with unfathomable loss. Tom Bell, Washington Post, 28 Oct. 2023 The stories skate along the edge of the familiar and the inexplicable, recounted with a sort of bewilderment and tenderness that suggests the modern world has made unfathomable misfits of us all. Salar Abdoh, Foreign Affairs, 24 Oct. 2023 There’s no way to explain or justify how knuckle-dragging low the San Diego State football program feels after an unfathomable, unexplainable 6-0 loss to Nevada on Saturday. Bryce Miller, San Diego Union-Tribune, 22 Oct. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'unfathomable.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1640, in the meaning defined above

Time Traveler
The first known use of unfathomable was in 1640

Dictionary Entries Near unfathomable

Cite this Entry

“Unfathomable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unfathomable. Accessed 30 Nov. 2023.

Kids Definition


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

More from Merriam-Webster on unfathomable

Last Updated: - Updated example sentences
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