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Synonyms

laborious

American  
[luh-bawr-ee-uhs] / ləˈbɔr i əs /

adjective

  1. requiring much work, exertion, or perseverance.

    a laborious undertaking.
    Synonyms:
    wearisome, tiresome, hard, difficult, burdensome, onerous, arduous, toilsome

  2. characterized by or requiring extreme care and much attention to detail.

    laborious research.

  3. characterized by or exhibiting excessive effort, dullness, and lack of spontaneity; labored: labor.

    a strained, laborious plot.

  4. given to or diligent in work.

    a careful, laborious craftsman.
    Synonyms:
    painstaking, sedulous, assiduous, industrious, hardworking
laborious British  
/ ləˈbɔːrɪəs /

adjective

  1. involving great exertion or long effort

  2. given to working hard

  3. (of literary style, etc) not fluent

"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

Other Word Forms

  • laboriously adverb
  • laboriousness noun
  • quasi-laborious adjective
  • superlaborious adjective
  • superlaboriousness noun
  • unlaborious adjective
  • unlaboriousness noun

Etymology

Origin of laborious

First recorded in 1350–1400; Middle English word from Latin word labōriōsus. See labor, -ious

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.