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

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 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 was a synonym of our modern embrace: to fathom someone was to clasp the person in your arms. By the 1600s fathom had taken to the seas, as the verb was used to mean "to measure by a sounding line." At the same time, the verb also developed senses synonymous with probe or investigate, and it 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 So much so that, today’s young girls can’t even fathom not being able to play their sports or go to medical school. Jordan Ligons, Essence, 21 June 2022 The fact that Saget, who died yesterday in Florida at age 65, won’t be around for either a cure or for that celebratory conversation is something Evnin can’t fathom. Chris Gardner, The Hollywood Reporter, 10 Jan. 2022 This might be hard to fathom, but training your chest shouldn't be solely focused on exercises that target the chest. Jeff Tomko, Men's Health, 26 July 2022 Hard to fathom the blatant stupidity that went behind the Raiders’ decision to organize a group-stomp on the Chiefs’ logo before the game at Kansas City (a 48-9 loss). Bruce Jenkins, San Francisco Chronicle, 17 Dec. 2021 More important is the large-scale disruption of lives, which would be hard to fathom. Michael Smolenscolumnist, San Diego Union-Tribune, 19 June 2022 Tatum’s father, Justin, still finds the connections of the families hard to fathom. Globe Staff, BostonGlobe.com, 31 May 2022 According to a source in the event business, who asked to speak on condition of anonymity, the appeal of the Abramovich bashes wasn’t hard to fathom. David Browne, Rolling Stone, 30 May 2022 Tuesday's elementary school massacre in Uvalde, Texas, was viewed internationally as just the latest in a long list of domestic American bloodshed that from the outside is increasingly hard to fathom. Alexander Smith, NBC News, 25 May 2022 See More

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.

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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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 12 Aug. 2022.

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More Definitions for fathom


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

More from Merriam-Webster on fathom

Nglish: Translation of fathom for Spanish Speakers

Britannica English: Translation of fathom for Arabic Speakers

Britannica.com: Encyclopedia article about fathom


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