fathom

[ fath-uhm ]

See synonyms for: fathom fathomed fathoming fathoms on Thesaurus.com

noun,plural fath·oms, (especially collectively) fath·om.

a unit of length equal to six feet (1.8 meters): used chiefly in nautical measurements. Abbreviation: fath

verb (used with object)

to measure the depth of by means of a sounding line; sound.
to penetrate to the truth of; comprehend; understand: to fathom someone's motives.

Origin of fathom

First recorded before 900; Middle English fathme, Old English fæthm “span of outstretched arms”; cognate with German Faden “six-foot measure,” Old Norse fathmr; akin to Latin patēre “to stand open” (see patent)

Other words from fathom

fath·om·a·ble, adjective
fath·om·er, noun
un·fath·om·a·ble, adjective
un·fath·omed, adjective

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use fathom in a sentence

My confidence is now forever and irreparably shaken for reasons I never could have fathomed.
The Aurora Shooting Made One Prominent Hollywood Producer Too Scared to Go to The Multiplex | Rick Schwartz | August 26, 2012 | THE DAILY BEAST
But he seems never to have fully fathomed why Wasserstein bought New York magazine in the first place.
Life After Wasserstein | Ralph Gardner, Jr. | December 14, 2009 | THE DAILY BEAST
Why he ever came amongst us none ever knew; it was a mystery we never fathomed.
Fifty Years of Railway Life in England, Scotland and Ireland | Joseph Tatlow
He fathomed every complication of heart and mind in the modern woman by an intuition of the laws which control her development.
Repertory Of The Comedie Humaine, Complete, A -- Z | Anatole Cerfberr and Jules Franois Christophe
Lin, in some way known only to herself, had fathomed Alfred's plans; she even knew the backer's name.
Watch Yourself Go By | Al. G. Field

Eyes that would bear a world of looking in, before their depth was fathomed.
A Budget of Christmas Tales by Charles Dickens and Others | Various
He fathomed not the unchanging love that had of late struggled into existence in the dreamy maiden's breast.
Baron Bruno | Louisa Morgan

British Dictionary definitions for fathom

fathom

/ (ˈfæðəm) /

noun

a unit of length equal to six feet (1.829 metres), used to measure depths of water
mining a unit of volume usually equal to six cubic feet, used in measuring ore bodies

forestry a unit of volume equal to six cubic feet, used for measuring timber

verb(tr)

to measure the depth of, esp with a sounding line; sound
to penetrate (a mystery, problem, etc); discover the meaning of

Origin of fathom

Old English fæthm; related to Old Frisian fethem outstretched arms, Old Norse fathmr embrace, Old High German fadum cubit, Latin patēre to gape

Derived forms of fathom

fathomable, adjective
fathomer, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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