[ahr-joo-uhs or, esp. British, ahr-dyoo-]


requiring great exertion; laborious; difficult: an arduous undertaking.
requiring or using much energy and vigor; strenuous: making an arduous effort.
hard to climb; steep: an arduous path up the hill.
hard to endure; full of hardships; severe: an arduous winter.

Origin of arduous

1530–40; < Latin arduus erect, steep, laborious; see -ous
Related formsar·du·ous·ly, adverbar·du·ous·ness, nounsu·per·ar·du·ous, adjectivesu·per·ar·du·ous·ly, adverbsu·per·ar·du·ous·ness, nounun·ar·du·ous, adjectiveun·ar·du·ous·ly, adverbun·ar·du·ous·ness, noun

Synonyms for arduous

Antonyms for arduous

1. easy. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for arduously

difficultly, heavily, laboriously, exhaustingly

Examples from the Web for arduously

Historical Examples of arduously

  • She studied music, arduously playing accompaniments for her mother.


    James Huneker

  • It was as if every morning that ship had been arduously explored with—with toothbrushes.


    Joseph Conrad

  • "You have been working most arduously, Senor Carson," said Quesada.

    The Wolf Cub

    Patrick Casey

  • Gifted with a naturally fine organ, he has cultivated it arduously and to excellent purpose.

    Vocal Mastery

    Harriette Brower

  • Arduously, but without avail, she searched through all the drawers and cupboards of the Rattle-Pane kitchen.

    Peace on Earth, Good-will to Dogs

    Eleanor Hallowell Abbott

British Dictionary definitions for arduously



requiring great physical or mental effort; difficult to accomplish; strenuous
hard to endure; harsharduous conditions
hard to overcome or surmount; steep or difficultan arduous track
Derived Formsarduously, adverbarduousness, noun

Word Origin for arduous

C16: from Latin arduus steep, difficult
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 arduously



1530s, "hard to accomplish, difficult to do," from Latin arduus "high, steep," also figuratively, "difficult," from PIE root *eredh- "to grow, high" (see ortho-). Literal sense of "high, steep, difficult to climb," attested in English from 1709.

Online Etymology Dictionary, © 2010 Douglas Harper