un·​fath·​om·​able | \ˌən-ˈfa-t͟hə-mə-bəl \

Definition of unfathomable 

: not capable of being fathomed:

a : immeasurable

b : impossible to comprehend

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Other Words from unfathomable

unfathomably \ˌən-​ˈfa-​t͟hə-​mə-​blē \ adverb

Examples of unfathomable in a Sentence

His behavior is completely unfathomable. the unfathomable reaches of space

Recent Examples on the Web

But the Seahawks rushed for an almost unfathomable 273 yards despite Chris Carson’s absence and Jordan Simmons seeing his first NFL action at right guard in place of D.J. Fluker. Bob Condotta, The Seattle Times, "The Final Word: Bob Condotta breaks down what went wrong in the Seahawks’ close loss to the Rams," 13 Nov. 2018 The addition of Amazon would raise Ambrose's plan to an almost unfathomable level of transformation. James Briggs, Indianapolis Star, "How a little-known Indianapolis developer got in position to land Amazon's HQ2," 3 June 2018 The region, defined as much by its 13,000-foot passes, striated rock formations, and colorful stupas as by its almost unfathomable remoteness, was, until 2011, accessible only by foot, horseback, or private aircraft. Debbie Pappyn, Condé Nast Traveler, "Trekking Nepal's Upper Mustang, a Pristine Corner of the Himalayas," 15 Oct. 2018 As someone who has worked in libraries for seven years, the suggestion that Amazon could be a better provider than a library is unfathomable. Amanda Oliver, Vox, "I’m a librarian. Amazon could never replace what I do.," 26 July 2018 Of course, many other memorials tell the story of the Shoah in its unfathomable immensity, but the Musée Nissim de Camondo, now a branch of Les Arts Décoratifs, is not exactly a memorial. James Mcauley, Town & Country, "A Secret Paris Museum and an Aristocratic Family Decimated by the Holocaust," 9 Feb. 2017 This was a strikingly notable incident of a bright player foreseeing a seemingly unfathomable situation, and executing the actions to put him into it. SI.com, "Kylian Mbappé's Announces Himself on the World Stage as Cristiano Ronaldo & Lionel Messi Bow Out," 2 July 2018 Or, worse, elicit a seemingly unfathomable, knee-jerk hatred. Stefan Stevenson, star-telegram, "The best viral high school baseball video brings out worst in Internet," 12 June 2018 On the perimeter, sharpshooters Danielle Kunk and Caitlin McEldowney combined for eight 3-pointers as Versailles went on an unfathomable 49-6 run to ignite the running clock going into the final stanza. Shelby Dermer, Cincinnati.com, "Summit Country Day, Williamsburg fall in regional semifinals," 7 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unfathomable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of unfathomable

1640, in the meaning defined above

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Statistics for unfathomable

Last Updated

8 Dec 2018

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Time Traveler for unfathomable

The first known use of unfathomable was in 1640

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English Language Learners Definition of unfathomable

: impossible to understand

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