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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.

    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

Etymology

Origin of laborious

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

Explanation

Laborious describes something that requires a lot of hard work, such as Victor Frankenstein’s laborious undertaking of digging graves to find monster parts. Laborious comes from the familiar word for work, labor, which doesn’t veer far from its roots in Old French meaning "exertion of the body," and from Latin “toil, pain, exertion, fatigue.” Anything that requires blood, sweat, and tears is laborious, and while it’s usually a good thing to work hard, laborious can also describe something over-thought, such as the heavy-handed plot of a bad TV show. Think labor plus boring, said like an old-fashioned English aristocrat: luh-bohr-ee-uhs.

Keep Reading on Vocabulary.com

Vocabulary lists containing laborious

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.

Exhausting, laborious, oppressive, but three points and hope.

From BBC • Jun. 14, 2026

Cooking a full-fledged meal from scratch seems too laborious.

From Salon • Jun. 6, 2026

I do fear that if you start selling your friends’ goods without their help, the sale will begin to feel more laborious than fun.

From MarketWatch • May 28, 2026

But the process of limiting the use of technology can be laborious.

From The Wall Street Journal • May 5, 2026

Other instances are Eli Whitney’s 1794 invention of his cotton gin to replace laborious hand cleaning of cotton grown in the U.S.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

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