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 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 However, the modern dive watch dates back to the mid-1950s, when Blancpain's 50 Fathoms and Rolex's Submariner both appeared. Steve Dool, CNN, "Understated but 'never easy': Why collectors covet Patek Philippe," 18 July 2017 Time traveling below the waves Dropping 10 fathoms down, below the green waves of the Gulf and back in time to this prehistoric world amounts to a sort of time traveler's journey. Ben Raines, NOLA.com, "Gulf's 60,000-year-old underwater forest spills its secrets in new documentary," 25 June 2017 Recent Examples on the Web: Verb Some people can't fathom paying into a depreciating asset, while others love getting a shiny new set of wheels every three years. Lizz Schumer, Good Housekeeping, "Leasing vs. Buying a Car: How to Decide What's Right for You," 1 Aug. 2019 Most adults can’t really fathom death’s irreversibility, either. Amy Dickinson, Detroit Free Press, "Dad needs to tell young sons their mom is dead," 19 Mar. 2018 Transgender men and women were unfamiliar to many, and hard to fathom. Martin J. Smith, Los Angeles Times, "He made this town the world’s ‘sex-change capital,’ but he’s not honored here," 12 Sep. 2019 And precious few visit, mostly scientists trying to fathom the secrets of its forbidding environment. David Holahan, USA TODAY, "'The Ice at the End of the World' review: Scary clues of climate change in Greenland," 11 June 2019 Perhaps because the stable universe Rivers occupies is so hard to fathom, his health gets taken for granted or overlooked. Tom Krasovic, San Diego Union-Tribune, "Column: Rivers is why Chargers’ “injury luck” is better than often portrayed," 20 Aug. 2019 It’s hard to describe—hard to fathom, even—that a single image can telescope in on itself the way this painting does. Duff Mcdonald, WIRED, "The Cosmic, Psychedelic, Glow-in-the-Dark Art of Alex Aliume," 20 Aug. 2019 His older brother, Roy Knight III told the local Weatherford Democrat newspaper that the end of the half century journey was hard to fathom. Author: Reis Thebault, Anchorage Daily News, "Southwest Airlines flew the remains of a Vietnam airman home to Dallas. The pilot was his son.," 9 Aug. 2019 And now, to learn that I will be given one of the prestigious Kennedy Center Honors, seems hard to fathom. Peggy Mcglone, Washington Post, "‘Sesame Street,’ Sally Field and Linda Ronstadt are among this year’s recipients of the Kennedy Center Honors," 18 July 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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Statistics for fathom

Time Traveler for fathom

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

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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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Comments on fathom

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a calculated move

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