UNRELIABLE Synonyms: 70 Similar and Opposite Words

unreliable

adjective

Definition of unreliable

as in erratic

likely to change frequently, suddenly, or unexpectedly I wouldn't count on him to show up for the play—he's pretty unreliable. She drives her car locally, but worries it's too unreliable for longer trips.

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Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of unreliable Writing a letter is interrupted by demanding people and unreliable machines, by illness and trouble. — Literary Hub, 13 July 2026 This saves you the trouble of relying on potentially unreliable mobile networks to reach your destination. — Jordan Minor, PC Magazine, 13 July 2026 Where most device makers at the time were worried about camera megapixels and color screens, Nokia had leapfrogged its competition with a back-to-basics phone that could survive the rain, endure unreliable power grids, and light the way home. — IEEE Spectrum, 13 July 2026 Voters are paying for aging, dirty and unreliable coal plants that often aren’t even running or working. — David Kieve, Time, 10 July 2026 See All Example Sentences for unreliable

Recent Examples of Synonyms for unreliable

Adjective

Dolphins are the outlier, with a genetic quirk that produces an erratic sleep pattern not fitting neatly into the other three.

— Hanna Wickes, Kansas City Star, 22 July 2026
An erratic sleeper whose pattern does not fit neatly into any other category.

— Hanna Wickes, Charlotte Observer, 22 July 2026

Definition of erratic

Adjective

With such a shaky sense of purpose, is John Sugar prepared to wade through to the other side of these rancid waters?

— Andy Andersen, Vulture, 17 July 2026
Unfortunately, what Ten Hag was trying to build was on shaky foundations, which crumbled quickly in the following campaign, despite an unlikely FA Cup final victory.

— Chris McKenna, New York Times, 16 July 2026

Definition of shaky

Adjective

What the lawsuit alleges The lawsuit alleges violations of the California Environmental Quality Act and that the project is inconsistent with the county’s general plan.

— Graham Womack, Sacbee.com, 17 July 2026
The challenge arises when founders pursue goals that are inconsistent with their personal values or definition of success.

— Nadia AlShomali, Forbes.com, 17 July 2026

Definition of inconsistent

Adjective

And then there’s Kimberly’s home life, which features an emotionally and physically fragile mom preparing to give birth and an undependable alcoholic father.

— Rob Hubbard, Twin Cities, 25 Feb. 2026
Yasmin, who was ousted from Pierpoint after a tabloid scandal involving her publishing-magnate father threatened to sully the bank by association, has turned to another undependable man for salvation, proposing to an aristocratic failson called Sir Henry Muck (Kit Harington).

— Inkoo Kang, New Yorker, 9 Feb. 2026

Definition of undependable

Adjective

Indeed, El Niño’s complexity limited the researchers’ simulations to two years; beyond that, the model becomes untrustworthy.

— Cody Cottier, Scientific American, 8 July 2026
The local gendarmerie, led by blandly untrustworthy Inspector Marchal (Bertrand Belin) is called in to investigate.

— Jessica Kiang, Variety, 16 June 2026

Definition of untrustworthy

Adjective

The ensemble drama traces the unpredictable shape of grief and family dynamics, aiming for an emotionally candid portrait of loss and the ties that hold communities together.

— Naman Ramachandran, Variety, 17 July 2026
In an increasingly unpredictable business environment, executives seek control over their biology through peptides, promising faster recovery and improved performance.

— Julian Hayes II, Forbes.com, 17 July 2026

Definition of unpredictable

Adjective

Stocks pulled back on Friday , capping off another volatile week.

— Jeff Marks,Paulina Likos, CNBC, 17 July 2026
That’s because wildfire smoke contains gases like nitrogen oxides and volatile organic compounds, which react in the sun and heat to create ground-level ozone.

— Kasha Patel, CNN Money, 17 July 2026

Definition of volatile

Browse Nearby Words

unreliability

unreliable

unreluctant

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“Unreliable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unreliable. Accessed 24 Jul. 2026.

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Synonyms of unreliable

adjective

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