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 Yet a 2023 Stanford study said that Pangram was biased against non-native English speakers, who might have more limited vocabularies, and many AI researchers contend that such detectors are unreliable. — Cameron Pugh, Christian Science Monitor, 12 Aug. 2026 The bus is both faraway and unreliable, and the bike ride is harrowing. — Nina Moskowitz, Bon Appetit Magazine, 6 Aug. 2026 Realbotix says those guardrails are designed to block inappropriate responses and reduce unreliable outputs. — Jesse Watson, FOXNews.com, 3 Aug. 2026 Chemical cues floating in the air in the natural environment are often sparse and unreliable. — Jacek Krywko, ArsTechnica, 1 Aug. 2026 See All Example Sentences for unreliable

Recent Examples of Synonyms for unreliable

Adjective

However, as global heat increases, the rain is becoming more erratic and intense, creating the conditions for deadly floods.

— ABC News, ABC News, 18 Aug. 2026
Those might include escalating consumption, erratic behavior, drinking alone, secretly drinking and drinking during the day.

— Melissa Rudy, FOXNews.com, 17 Aug. 2026

Definition of erratic

Adjective

But with his shaky return from arthroscopic elbow surgery leading to three blown saves in four appearances, the crowd tempered its enthusiasm appropriately.

— Maddie Lee, Los Angeles Times, 15 Aug. 2026
And reactions tend to get built on shaky ground, which is where the real cost shows up.

— Dan Haiem, Forbes.com, 12 Aug. 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

Lawyers representing Elon Musk, who sued OpenAI, Altman and Brockman in 2024 over a dispute about the company's corporate structure, used Altman's firing as a way to cast doubt on his character, accusing him of being untrustworthy.

— Ashley Capoot,Kate Rooney, CNBC, 14 Aug. 2026
The forest of myth was an eerie, volatile place, a shelter for untrustworthy and unpredictable characters who might eat you as soon as look at you.

— Literary Hub, Literary Hub, 30 July 2026

Definition of untrustworthy

Adjective

Some have been Ukrainian drones knocked off course by Russian electronic warfare, such as the jamming of navigation signals, which can make their flight paths unpredictable and complicate decisions about whether and where to shoot them down.

— Elsa Ohlen, CNBC, 14 Aug. 2026
Carefully evaluate both options, then, before making a final decision and don't discount the advantages of splitting your funds between both account types, which may be your best recourse in today's still uneven and unpredictable economic terrain.

— Matt Richardson, CBS News, 13 Aug. 2026

Definition of unpredictable

Adjective

At the same time, categorical funding can be unstable from year to year due to changing priorities and how much money the state has to appropriate.

— Jason Burns, The Conversation, 17 Aug. 2026
Inside a fusion machine, the plasma can reach temperatures hotter than the Sun’s core while powerful magnetic fields squeeze it into a tiny, unstable space.

— Rupendra Brahambhatt, Interesting Engineering, 16 Aug. 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 21 Aug. 2026.

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Synonyms of unreliable

adjective

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