[ ahr-joo-uhs or, especially British, ahr-dyoo- ]
/ ˈɑr dʒu əs or, especially British, ˈɑr dyu- /


requiring great exertion; laborious; difficult: an arduous undertaking.
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.

Origin of arduous

1530–40; <Latin arduus erect, steep, laborious; see -ous

OTHER WORDS FROM arduous Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for arduous

British Dictionary definitions for arduous

/ (ˈɑːdjʊəs) /


requiring great physical or mental effort; difficult to accomplish; strenuous
hard to endure; harsharduous conditions
hard to overcome or surmount; steep or difficultan arduous track

Derived forms of arduous

arduously, adverbarduousness, noun

Word Origin for arduous

C16: from Latin arduus steep, difficult
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012