arduous
Americanadjective
-
requiring great exertion; laborious; difficult.
an arduous undertaking.
- Synonyms:
- exhausting, burdensome, wearisome, onerous, toilsome, hard
- Antonyms:
- easy
-
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.
adjective
-
requiring great physical or mental effort; difficult to accomplish; strenuous
-
hard to endure; harsh
arduous conditions
-
hard to overcome or surmount; steep or difficult
an arduous track
Other Word Forms
Etymology
Origin of arduous
First recorded in 1530–40; from Latin arduus “erect, laborious, steep”
Explanation
Use the adjective arduous to describe an activity that takes a lot of effort. Writing all those college essays and filling out the applications is an arduous process! Arduous was first used in English to mean "steep" or "difficult to climb." If you're an outdoorsman, hiking up a mountain is a lot of fun, but if you're a couch potato, it's an arduous trek. Today, the word can be used figuratively for something that is difficult or takes a lot of work. If you spend an arduous week studying for your final exams, you'll do well because you've worked really hard!
Vocabulary lists containing arduous
100 SAT Words Beginning with "A"
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30 GRE Words Beginning with "A"
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Grade 10, List 2
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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.
He agrees that tech should help to “relieve humans of arduous, repetitive or dangerous tasks” and “provide intelligent support,” but also warns of growing A.I.-induced inequality, which exacerbates poverty and forced migration.
From Slate • May 28, 2026
After facing Crystal Palace in Krakow, Poland, in the first leg of their Uefa Conference League semi-final on Thursday, the Ukrainian Premier League leaders will begin an arduous journey.
From BBC • Apr. 30, 2026
There was no shortage of ideas for other ways to ease the financial burdens facing Californians, but few specifics on how they would deliver on those promises given the state’s complex and arduous legislative process.
From Los Angeles Times • Apr. 29, 2026
Even as Gulf tanker traffic slowly resumes, the road back to normal food production will be long and arduous, given the war's impact on fertiliser supplies, the UN has warned.
From Barron's • Apr. 10, 2026
Openly, Bobby disparaged how he’d performed, but the Soviet chess establishment was dazzled by how he managed to place so high under such arduous conditions.
From "Endgame" by Frank Brady
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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.