/ Dictionary / Index A arduous: Meaning and Definition of Find definitions for: ar•du•ous Pronunciation: (är'j-us or, esp. Brit., är'dy-), [key] — adj. 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. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: arduous (Thesaurus) ARDS are Related Content Daily Word Quiz: crockery Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language