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 Zeller van Almsick and Exile cite high costs and unreliable sales. — Brian Boucher, ARTnews.com, 5 Nov. 2026 There was a time in this country when arts criticism was valued as a worthwhile pursuit unto itself, as opposed to a wonky and unreliable component of the promotional apparatus. — David Ehrlich, IndieWire, 3 Nov. 2026 In Fastagger’s case, that meant finding a way to make their models work despite inexpensive phones, unreliable internet connections, and business records that may consist of little more than mobile-money transactions. — IEEE Spectrum, 3 Nov. 2026 Courts so far have sided with California and Los Angeles County's arguments that the federal government's list is unreliable, and that creating a novel system to segregate ballots while voting is already underway is infeasible. — Jude Joffe-Block, NPR, 2 Nov. 2026 See All Example Sentences for unreliable

Recent Examples of Synonyms for unreliable

Adjective

Experts are warning Connecticut motorists to stay alert as the chances of colliding with deer are greatest during the final months of the year as white-tail deer mating season makes the animals more erratic and dangerous.

— Stephen Underwood, Hartford Courant, 7 Nov. 2026
Meanwhile, neither of these games appears to have been optimized for the M5 Ultra's 80 GPU cores within the Mac Studio desktop, hence the erratic comparative results throughout.

— Joe Osborne, PC Magazine, 5 Nov. 2026

Definition of erratic

Adjective

McCord won’t have much help in the form of experienced wide receivers or tight ends, and his pass protection will probably be shaky.

— Chris Perkins, Sun Sentinel, 11 Nov. 2026
With shaky quarterback play, expect the Wildcats to lean on their duo.

— Steven Johnson, Fort Worth Star-Telegram, 10 Nov. 2026

Definition of shaky

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

Perhaps the arrival of fall and winter, and with it rougher and more unpredictable seas, will reduce the flow.

— Pedro Portal, Miami Herald, 12 Nov. 2026
Potential applications include manufacturing, space exploration and search-and-rescue missions, where robots may need to navigate unpredictable environments, manipulate objects and adapt to changing requirements.

— Jijo Malayil, Interesting Engineering, 12 Nov. 2026

Definition of unpredictable

Adjective

Technology stocks — a key driver of rallies in recent years — have been notably volatile in 2026.

— Chloe Taylor, CNBC, 11 Nov. 2026
In the case of foods and certain beverages, breakdown of the amino acids results in volatile Strecker aldehydes, which are responsible for aroma, and in aminoketones, which impart flavor and coloration, particularly browning.

— Encyclopedia Britannica, Encyclopedia Britannica, 9 Nov. 2026

Definition of volatile

Adjective

The glow of many Turners has dwindled, thanks to unstable pigments, but here is an immaculate exception.

— Anthony Lane, New Yorker, 5 Nov. 2026
And while unstable coalitions repeatedly fused and dissolved in the halls of power, outside these halls pipes burst and roads crumbled.

— Ryan Lenora Brown, Christian Science Monitor, 5 Nov. 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 13 Nov. 2026.

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Synonyms of unreliable

adjective

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