Dictionary.com
definitions
  • synonyms

fathom

[fath-uh m]
See more synonyms on Thesaurus.com
noun, plural fath·oms, (especially collectively) fath·om.
  1. a unit of length equal to six feet (1.8 meters): used chiefly in nautical measurements. Abbreviation: fath
Show More
verb (used with object)
  1. to measure the depth of by means of a sounding line; sound.
  2. to penetrate to the truth of; comprehend; understand: to fathom someone's motives.
Show More

Origin of fathom

before 900; Middle English fathme, Old English fæthm span of outstretched arms; cognate with German Faden six-foot measure, Old Norse fathmr; akin to patent
Related formsfath·om·a·ble, adjectivefath·om·er, nounun·fath·om·a·ble, adjectiveun·fath·omed, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for fathom

Contemporary Examples

Historical Examples

  • Sixty fathom of two-inch chain, and old Joe talks about parting.

    Malbone

    Thomas Wentworth Higginson

  • But any attempt on his part to fathom it only met with cold silence.

    K

    Mary Roberts Rinehart

  • "There's less than a fathom of water here, sir," sang out Johnson from the bows.

  • The look in his eyes was both sad and savage--an expression I could not fathom.

    In the Valley

    Harold Frederic

  • Miss Hernshaw didn't seek to fathom the mystery of his closing words.

    Questionable Shapes

    William Dean Howells


British Dictionary definitions for fathom

fathom

noun
  1. a unit of length equal to six feet (1.829 metres), used to measure depths of water
  2. mining a unit of volume usually equal to six cubic feet, used in measuring ore bodies
  3. forestry a unit of volume equal to six cubic feet, used for measuring timber
Show More
verb (tr)
  1. to measure the depth of, esp with a sounding line; sound
  2. to penetrate (a mystery, problem, etc); discover the meaning of
Show More
Derived Formsfathomable, adjectivefathomer, noun

Word Origin

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

Word Origin and History for fathom

n.

Old English fæðm "length of the outstretched arm" (a measure of about six feet), also "arms, grasp," and, figuratively "power," from Proto-Germanic *fathmaz "embrace" (cf. Old Norse faðmr "embrace, bosom," Old Saxon fathmos "the outstretched arms," Dutch vadem "a measure of six feet"), from PIE *pot(e)-mo-, from root *pete- "to spread, stretch out" (see pace (n.)). There are apparent cognates in Old Frisian fethem, German faden "thread," which OED explains by reference to "spreading out."

Show More

v.

Old English fæðmian "to embrace, surround, envelop;" see fathom (n.). The meaning "take soundings" is from c.1600; its figurative sense of "get to the bottom of, understand" is 1620s. Related: Fathomed; fathoming.

Show More
Online Etymology Dictionary, © 2010 Douglas Harper