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Definitions

arduous

[ahr-joo-uhs, ahr-dyoo-] / ˈɑr dʒu əs, ˈɑr dyu- /
ADJECTIVE
difficult, hard to endure
Synonyms
STRONGEST
backbreaking burdensome exhausting formidable grueling laborious onerous painful rigorous strenuous tiring tough troublesome trying uphill
WEAK
fatiguing harsh heavy labored murder no picnic punishing rough severe taxing toilsome
Antonyms
STRONGEST
easy effortless facile helpful mild nice pleasant trivial weak
WEAK
motivating

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

Reasonover had the arduous task of replacing fan favorite Perrette, who left the show after 15 seasons in 2018.

From Los Angeles Times • Mar. 24, 2026

It was the summer of 2016, and my family and I were travelling back to the States from Bangladesh — an arduous 23-hour-long journey that was further extended by a 12+ hour layover in Istanbul.

From Salon • Mar. 21, 2026

He is on his own journey, one that will be arduous and long, filled with missteps and stumbles.

From "Vincent and Theo: The Van Gogh Brothers" by Deborah Heiligman

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.