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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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Regulatory shortcuts exist that would allow the FDA to skip the more laborious approval process.

From Salon • Apr. 4, 2026

“While we have tried to simplify the underlying concepts behind the Ontology model, building and implementing an Ontology in a large enterprise is a laborious process,” the analysts say.

From Barron's • Mar. 20, 2026

The pharma giants will still have other moats, notably the laborious regulatory and testing regime as well as distribution.

From MarketWatch • Mar. 17, 2026

She wanted to digitise and streamline those laborious tasks into a piece of tech that she can view on her cellphone or computer.

From BBC • Jan. 19, 2026

Then he set about the laborious task of transcribing it into code and addressed it in an ordinary envelope to an insignificant part of central London.

From "The Book of Dust: La Belle Sauvage" by Philip Pullman