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 Holmes was willing to put unreliable blood-test results in the hands of patients and, even after that fraud was exposed, Fielder showed us investors still willing to support her efforts to get back into the biotech game. — Maxwell Adler, Vanity Fair, 27 Oct. 2026 Incomplete and unreliable demographic data could distort how trillions of federal dollars are distributed across hundreds of programs such as Medicaid, SNAP, WIC, and Head Start. — Julie Morita, Time, 25 Oct. 2026 That makes checking the model name alone an unreliable way to confirm authenticity. — Kurt Knutsson, FOXNews.com, 23 Oct. 2026 Yet, the company’s machines really could only perform a limited number of tests and often produced unreliable results. — Marco Quiroz-Gutierrez, Fortune, 21 Oct. 2026 See All Example Sentences for unreliable

Recent Examples of Synonyms for unreliable

Adjective

Climate change also brings increasingly erratic storm systems, heat and rainfall patterns that leave standing water, creating conditions ideal for mosquitoes to breed.

— Kylee Rae Noel, The Conversation, 27 Oct. 2026
Baseball is an ensemble game, a wildly erratic sport to predict.

— Brady Brickner-Wood, New Yorker, 26 Oct. 2026

Definition of erratic

Adjective

This time around, both teams are coming in after inconsistent regular seasons, but both have been much better over the last five weeks.

— Steve Millar, Chicago Tribune, 22 Oct. 2026
The association with the Human Rights Campaign could create more confusion about Talarico’s stance on the medical issue, as his position has come into question through his inconsistent comments.

— Hudson Crozier, The Washington Examiner, 21 Oct. 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

Today’s Theme At 60-Across, we’re asked for a term that describes something [Like an untrustworthy business] — which, the revealer clue suggests, doubles as [a hint to the ends of 17-, 29-, 39- and 47-Across].

— Sam Corbin, New York Times, 27 Oct. 2026
Platner’s noisy ascension and implosion didn’t just leave the Democrats looking untrustworthy.

— Chris Smith, Vanity Fair, 26 Oct. 2026

Definition of untrustworthy

Adjective

Rashida Jones and Will McCormack wrote the screenplay for the film that follows two couples at a dinner party that turns into an unpredictable evening exposing messy relationships and desires.

— Beatrice Verhoeven, HollywoodReporter, 28 Oct. 2026
The Serbian leader had long been seen as an unpredictable annoyance, and his balancing act wasn’t particularly subtle.

— Brady Knox, The Washington Examiner, 27 Oct. 2026

Definition of unpredictable

Adjective

To their credit, the creative minds behind the Absolute series don’t bother masking their politics — an especially bold move for anyone working in an industry with an often reactive and volatile fandom.

— Christopher Cruz, Rolling Stone, 28 Oct. 2026
Still, the prospect of additional supply from American producers remains uncertain, with companies reluctant to commit to major new investments amid volatile prices and geopolitical risks.

— Lee Ying Shan, CNBC, 26 Oct. 2026

Definition of volatile

Adjective

Water essentially acts as a catalyst that spontaneously creates particles known as hydroxyl radicals, unstable molecules linked to aging and disease.

— Michael Hawthorne, Chicago Tribune, 22 Oct. 2026
If a tree appears diseased, unstable or at risk of falling, consider documenting the problem and notifying the owner in writing.

— Sacbee.com, Sacbee.com, 22 Oct. 2026

Definition of unstable

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 30 Oct. 2026.

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Synonyms of unreliable

adjective

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