Synonyms of arduous

arduous

adjective

ˈär-jə-wəs 

1

as in difficult

requiring considerable physical or mental effort

climbing Mount Everest is an arduous, exhausting challenge

Synonyms & Similar Words

• difficult
• challenging
• tough
• rigorous
• hard
• demanding
• formidable
• complicated
• strenuous
• effortful
• heavy
• laborious
• grueling
• rough
• rugged
• exhausting
• toilsome
• sweaty
• painful
• backbreaking
• severe
• herculean
• uphill
• tall
• testing
• exacting
• intricate
• murderous
• complex
• stiff
• killer
• serious
• problematic
• hellacious
• stressful
• annoying
• elusive
• onerous
• moiling
• tricky
• brutal
• pick-and-shovel
• involved
• grim
• burdensome
• Augean
• stubborn
• oppressive
• troublesome
• thorny
• abstruse
• abstract
• irksome
• labored
• recondite
• bruising
• insoluble
• hairy
• opaque
• knotty
• trying
• vexatious
• tight
• ticklish
• strict
• stringent
• bothersome
• spiny
• distressing
• taxing
• cruel
• grievous
• inhuman

Antonyms & Near Antonyms

• easy
• simple
• effortless
• light
• cheap
• soft
• undemanding
• facile
• mindless
• uncomplicated
• manageable
• clear
• elementary
• doable
• achievable
• smooth
• gentle
• painless
• soothing
• comforting
• relaxed
• accessible
• friendly
• user-friendly
• idiotproof

2

as in challenging

requiring much time, effort, or careful attention

the arduous task of doing the research for my term paper

Synonyms & Similar Words

• challenging
• difficult
• demanding
• laborious
• tough
• onerous
• burdensome
• grueling
• hard
• toilsome
• exacting
• strenuous
• taxing
• formidable
• killing
• testing
• persnickety
• rigorous
• herculean
• oppressive
• rough
• rugged
• stringent
• stiff
• trying
• severe
• strict
• rigid
• stern

Antonyms & Near Antonyms

• light
• undemanding
• easy
• simple
• smooth
• unchallenging
• effortless
• facile
• nondemanding

Synonym Chooser

How is the word arduous different from other adjectives like it?

The words difficult and hard are common synonyms of arduous. While all three words mean "demanding great exertion or effort," arduous stresses the need of laborious and persevering exertion.

the arduous task of rebuilding

When could difficult be used to replace arduous?

While in some cases nearly identical to arduous, difficult implies the presence of obstacles to be surmounted or puzzles to be resolved and suggests the need of skill or courage.

the difficult ascent of the mountain

When is it sensible to use hard instead of arduous?

The synonyms hard and arduous are sometimes interchangeable, but hard implies the opposite of all that is easy.

farming is hard work

Example Sentences

Recent Examples of arduous

In addition to late-arriving mail ballots, the California secretary of state told ABC News that there is an arduous process of counting mail ballots and validating voters' signatures, as each envelope signature must match the signatures on file. — ABC News, 28 Oct. 2026

There’s too much here to be effectively explored in a feature, even a 131-minute one whose length is all the more impressive given how arduous stop-motion is as a process. — Alison Willmore, Vulture, 23 Oct. 2026

Creative endeavor, in the space of a few hours, flashes its many faces, arduous and sexy, fleeting and fun. — Literary Hub, 16 Oct. 2026

Traditionally, the man of the house leads the caravan and sets up camp each night while the wife and kids have the arduous task of moving the goats, on top of household duties like preparing meals. — Jen Murphy, Condé Nast Traveler, 15 Oct. 2026

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