[ses-kwi-pi-dey-lee-uh n, -deyl-yuh n]

adjective Also ses·quip·e·dal [ses-kwip-i-dl] /sɛsˈkwɪp ɪ dl/.

given to using long words.
(of a word) containing many syllables.


a sesquipedalian word.

Origin of sesquipedalian

1605–15; < Latin sēsquipedālis measuring a foot and a half (see sesqui-, pedal) + -an
Related formsses·qui·pe·dal·i·ty [ses-kwi-pi-dal-i-tee] /ˌsɛs kwɪ pɪˈdæl ɪ ti/, ses·qui·pe·da·li·an·ism, ses·quip·e·dal·ism [ses-kwip-i-dl-iz-uh m, ‐kwi-peed-l-iz-uh m] /sɛsˈkwɪp ɪ dlˌɪz əm, ‐kwɪˈpid lˌɪz əm/, nounun·ses·qui·pe·da·li·an, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for sesquipedalian

Historical Examples of sesquipedalian

  • Fact was, he had monologued it in his most sesquipedalian phraseology.

  • The gentlemen with this sesquipedalian title control the railways or portions of railways in their own circles.

  • But "documentary evidence" was too sesquipedalian to submit to without a protest.

    When Ghost Meets Ghost

    William Frend De Morgan

  • He was indebted to a ruse of Aunt Margaret for his historic and sesquipedalian name.

  • D'Artagnan recoiled, as though the sesquipedalian syllables had knocked the breath out of his body.

    The Man in the Iron Mask

    Alexandre Dumas, Pere

British Dictionary definitions for sesquipedalian


less commonly sesquipedal (sɛsˈkwɪpədəl)


tending to use very long words
(of words or expressions) long and ponderous; polysyllabic


a polysyllabic word
Derived Formssesquipedalianism, noun

Word Origin for sesquipedalian

C17: from Latin sēsquipedālis of a foot and a half (coined by Horace in Ars Poetica), from sesqui- + pedālis of the foot, from pēs foot
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 sesquipedalian

1610s, "person or thing a foot and a half long," from Latin sesquipedalia "a foot-and-a-half long," from sesqui- "half as much again" (see sesqui-) + stem of pes "foot" (see foot (n.)). As an adjective 1650s.

Meaning "sesquipedalian word" (1830) is from Latin sesquipedalia verba "words a foot-and-a-half long," in Horace's "Ars Poetica" (97), nicely illustrating the thing he is criticizing.

Online Etymology Dictionary, © 2010 Douglas Harper