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 numberfive 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 fathomable (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 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, "After Overcoming a 'Band Mid-Life Crisis,' Lady Antebellum Plumbs the Depths in Ocean," 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, "The English language always has your number," 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, "Come Take a Tour of America's Newest Nuclear Submarine," 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, "Summer ocean fishing, fall hunting seasons set for Oregon," 20 Apr. 2018 Get ready to be terrified by the mysterious fathoms below! Laura Beck, Cosmopolitan, "The Trailer for 'Siren,' a Terrifying (and Kinda Sexy?!) New Show About Mermaids Is Freaky-as-Hell," 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, "Meandering the mudflats: 800 miles around Cook Inlet," 15 Sep. 2017 Captain Cook filled his logs with notes on the tide, on the time the ebb began each day, the force of the current, the fathoms of water, or lack of water, beneath his ship. Erin Mckittrick, Alaska Dispatch News, "Meandering the mudflats: 800 miles around Cook Inlet," 15 Sep. 2017 Twain's pen name originates from his time working with steamboats: Twain refers to a measure of length known as two fathoms (12 feet). Logan Sykes, Town & Country, "Happy 180th Birthday, Mark Twain! 16 Facts You Need to Know About The Author," 30 Nov. 2015 Recent Examples on the Web: Verb And under this current makeup, that's pretty hard to fathom at this point. NBC News, "Transcript: What About Pence?," 11 Nov. 2019 Not to us, of course, but to the pundits and fashionistas on either coast, the ones who don’t watch him every night, the ones who can’t fathom how a non-traditional frame and non-traditional game can somehow set the bar. Sean Keeler, The Denver Post, "How Nikola Jokic got his groove, and the Nuggets’ mojo, back on track," 10 Nov. 2019 Other Democrats could not fathom why people like me –– a progressive woman of color who advocates for representation — would support a 78-year-old white man for president. Linda Sarsour, Teen Vogue, "Yes, Women of Color Support Bernie Sanders. It’s Time to Stop Erasing Our Voices.," 11 Nov. 2019 So much had been invested in last season, the ultimate goal had seemingly moved within sight, that to be dispatched in that way was hard to fathom. Mike Berardino, Indianapolis Star, "'Natural-born leader' Alohi Gilman is a powerful voice for Notre Dame," 15 Nov. 2019 The widening and often-hard-to-fathom crackdown has even reached aging Soviet-era dissidents with scant means and few followers. Andrew Higgins, New York Times, "As Putin Era Begins to Wane, Russia Unleashes a Sweeping Crackdown," 25 Oct. 2019 Start with Doncic, the highest-rated of the three, yet also the one with the most hard-to-fathom criticisms of his game. Tim Bontemps, chicagotribune.com, "Luka Doncic, Trae Young and Michael Porter Jr. are the great NBA draft unknowns," 21 June 2018 There now are star players in this league who weren’t alive the last time San Antonio missed the playoffs, and veteran coaches who cannot fathom a reality in which the Spurs might not be good. Mike Finger, ExpressNews.com, "As Spurs slide, old belief is put to the test," 19 Nov. 2019 It’s hard to fathom similar concern in the U.S., where Boeing is regarded as a national champion and lawmakers are concerned about the risks posed by Commercial Aircraft Corp. of China Ltd., or Comac. Washington Post, "Boeing Max Return Has More Layers Than an Onion," 11 Nov. 2019

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

Time Traveler

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

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Statistics for fathom

Last Updated

29 Nov 2019

Cite this Entry

“Fathom.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/fathomable. Accessed 22 January 2020.

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More Definitions for fathom


How to pronounce fathom (audio)

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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