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.
The Via Alpina route is considered so arduous and technical that only a handful of runners have ever attempted it under formal timing.
From BBC ● Aug. 2, 2026
In 2025, London had 281,000 unbuilt homes—houses that were conditionally accepted but never built, often because the developer decided the conditions were too arduous.
From The Wall Street Journal ● Jul. 20, 2026
But because few theaters own the necessary equipment or employ full-time projectionists, coordinating a release as massive as “The Odyssey” is its own arduous journey.
From Los Angeles Times ● Jul. 17, 2026
Seaweed foraging on the rocky coastline at the edge of the Pacific Ocean can be arduous and dangerous, says Wu, whose passion has kept her going for more than half a century.
From Barron's ● Jun. 30, 2026
She became in the end more than their equal in all the arduous feats of a hunter’s life.
From "Mythology: Timeless Tales of Gods and Heroes" by Edith Hamilton
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.
