fath·​om | \ ˈfa-t͟həm How to pronounce fathom (audio) \

Definition of fathom

 (Entry 1 of 2)

1 : a unit of length equal to six feet (1.83 meters) used especially for measuring the depth of water sometimes used in the singular when qualified by a number five fathom deep
2 : comprehension the themes display a newer fathom than the technical modernism of the composer's earlier worksNewsweek


fathomed; fathoming; fathoms

Definition of fathom (Entry 2 of 2)

intransitive verb

1 : probe
2 : to take soundings

transitive verb

1 : to measure by a sounding line
2 : to penetrate and come to understand couldn't fathom the problem

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Other Words from fathom


fathomable \ ˈfa-​t͟hə-​mə-​bəl How to pronounce fathom (audio) \ adjective

Synonyms for fathom

Synonyms: Verb

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Did fathom Always Refer to a Measurement?


Fathom comes to us from Old English fæthm, meaning "outstretched arms." The noun fathom, which now commonly refers to a measure (especially of depth) of six feet, was originally used for the distance, fingertip to fingertip, created by stretching one's arms straight out from the sides of the body. In one of its earliest uses, the verb fathom meant to encircle something with the arms as if for measuring and was also a synonym for "embrace." In the 1600s, however, fathom took on the meaning of using a sounding line to measure depth. At the same time, the verb also developed senses synonymous with "probe" or "investigate," and is now frequently used to refer to the act of getting to the bottom of something (figuratively speaking).

Examples of fathom in a Sentence

Noun The water here is five fathoms deep. Verb the pilot had to continually fathom the river, which drought conditions had lowered to unprecedented levels
Recent Examples on the Web: Noun Musk’s tumble only underscores the hard-to-fathom velocity of his ascent. Devon Pendleton, Fortune, 6 Mar. 2021 But in today’s world of restrictions on size, quantity and season, releasing reef fish has become part of our new reality—as are the challenges of ensuring postrelease survival for an animal pulled up from 20 fathoms. Popular Science, 11 Feb. 2020 That impulse, growing out of one pivotal song, eventually pointed the way to the fathoms of Ocean, the group’s new album, their seventh, which debuts Friday. Nancy Kruh, PEOPLE.com, 15 Nov. 2019 The lines were marked at two, three, five, seven, 10, 13, 15, 17 and 20 fathoms. Richard Lederer, San Diego Union-Tribune, 19 Oct. 2019 The submarine is recorded in 1,805 fathoms of water, or 8,310 feet, and makes a test dive. Kyle Mizokami, Popular Mechanics, 7 Jan. 2019 Leadbetter Point to Cape Falcon - Nearshore (inside 40 fathoms) opens May 7; Mondays to Wednesdays until 500 pounds are caught or Sept. 30. Bill Monroe, OregonLive.com, 20 Apr. 2018 Get ready to be terrified by the mysterious fathoms below! Laura Beck, Cosmopolitan, 27 Jan. 2018 More than 200 years later, our low tide was at the same time Cook's high had been, and 4 fathoms — 24 feet — was an understatement. Erin Mckittrick, Alaska Dispatch News, 15 Sep. 2017 Recent Examples on the Web: Verb This isn’t necessarily for lack of talent but may stem from a host of other circumstances or factors over which the startup has no control – or cannot fathom. Akshay Bhargava, Forbes, 24 May 2021 Given the status quo in Palestine, the dual wallop of a pandemic alongside airstrikes conducted by their nuclear-capable ruling power is almost unbearable to fathom. Natalie Shure, The New Republic, 24 May 2021 In her hometown in Guatemala, a street gang had threatened Yesenia for not joining its ranks, and Verlyn could not fathom anything happening to her daughter. San Diego Union-Tribune, 7 May 2021 Much of the show’s conflict revolves around the fact that the aliens can’t fathom that humans bone sometimes. Eric Vilas-boas, Vulture, 5 Apr. 2021 Seems hard to fathom that when looking at Aldridge playing with LeBron James and Anthony Davis, who is still out with the calf strain. Pairing him up with Damian Lillard is scary, too, especially if Portland can return to full strength. Duane Rankin, The Arizona Republic, 16 Mar. 2021 As an unemployed single mother of two young children, Paige Benjamin has no emergency savings to fall back on and can’t fathom starting to invest at this stage of her life. USA Today, 15 Mar. 2021 And Fox has never been able to fathom the idea of Olsen hurting her daughters. Peggy O’hare, ExpressNews.com, 21 Jan. 2021 But Trump remains forever impenetrable in 280-character outbursts, which is why commentators have gone to such extreme lengths to dig up precedents that are easier to fathom. New York Times, 19 Jan. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fathom.' 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 fathom


before the 12th century, in the meaning defined at sense 1


1607, in the meaning defined at intransitive sense 1

History and Etymology for fathom

Noun and Verb

Middle English fadme, from Old English fæthm outstretched arms, length of the outstretched arms; akin to Old Norse fathmr fathom, Latin patēre to be open, pandere to spread out, Greek petannynai

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Time Traveler for fathom

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The first known use of fathom was before the 12th century

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Cite this Entry

“Fathom.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fathom. Accessed 15 Jun. 2021.

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More Definitions for fathom



English Language Learners Definition of fathom

 (Entry 1 of 2)

: a unit of length equal to six feet (about 1.8 meters) used especially for measuring the depth of water



English Language Learners Definition of fathom (Entry 2 of 2)

: to understand the reason for (something)


fath·​om | \ ˈfa-t͟həm How to pronounce fathom (audio) \

Kids Definition of fathom

 (Entry 1 of 2)

: a unit of length equal to six feet (about 1.8 meters) used chiefly in measuring the depth of water


fathomed; fathoming

Kids Definition of fathom (Entry 2 of 2)

1 : to understand the reason for something I couldn't fathom how he escaped punishment.
2 : to measure the depth of water by means of a special line


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