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
- arduously adverb
- arduousness noun
- superarduous adjective
- superarduously adverb
- superarduousness noun
- unarduous adjective
- unarduously adverb
- unarduousness noun
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.
Acquiring security clearances remained a long and arduous process.
From MarketWatch • Apr. 4, 2026
After an arduous, nearly two month long journey hiking through Thailand, Geumseong eventually made it to Seoul.
From BBC • Mar. 27, 2026
“Ghost Elephants” is a Werner Herzog film so, unsurprisingly, the titular characters play second fiddle to a man on an arduous quest, with fascinating digressions along the way.
From Los Angeles Times • Mar. 24, 2026
Between lofty investor expectations and ramping competition in the quantum industry, the road ahead is arduous.
From Barron's • Mar. 4, 2026
Not that it was easy—the journey was an arduous one, perhaps harder than the sea passage to Australia.
From "Sapiens: A Brief History of Humankind" by Yuval Noah Harari
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.
