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adjective ar·du·ous \ˈär-jə-wəs, -dyu̇-, -jü-əs\

Simple Definition of arduous

  • : very difficult

Full Definition of arduous

  1. 1 a :  hard to accomplish or achieve :  difficult <years of arduous training> b :  marked by great labor or effort :  strenuous <a life of arduous toil — A. C. Cole>

  2. 2 :  hard to climb :  steep <an arduous path>

ar·du·ous·ly adverb
ar·du·ous·ness noun

Examples of arduous

  1. Traveling for several days by train, stagecoach and horseback, they would reach Mariposa Grove, a stand of some 200 ancient giant sequoias, where they would rest before embarking on an arduous descent via 26 switchbacks into the valley. —Tony Perrottet, Smithsonian, July 2008

  2. As yoga classes go, this is not an arduous one, but the students don't know that. —Richard Corliss, Time, 23 Apr. 2001

  3. Women of middling means had the most to gain from increased consumption, for imported goods often reduced their long and arduous labor, especially in making candles and soap or in spinning and weaving cloth. —Alan Taylor, American Colonies, 2000

  4. He went through a long and arduous training program.

  5. an arduous journey across miles of desert

Origin of arduous

Latin arduus high, steep, difficult; akin to Old Irish ard high

First Known Use: 1538

Synonym Discussion of arduous

hard, difficult, arduous mean demanding great exertion or effort. hard implies the opposite of all that is easy <farming is hard work>. difficult implies the presence of obstacles to be surmounted or puzzles to be resolved and suggests the need of skill or courage <the difficult ascent of the mountain>. arduous stresses the need of laborious and persevering exertion <the arduous task of rebuilding>.

ARDUOUS Defined for Kids


adjective ar·du·ous \ˈär-jə-wəs\

Definition of arduous

  1. :  difficult 1 <an arduous climb>

ar·du·ous·ly adverb <working arduously>

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February 11, 2016

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