unreliable

adjective

un·​re·​li·​able ˌən-ri-ˈlī-ə-bəl How to pronounce unreliable (audio)
Synonyms of unreliablenext
: not reliable : undependable, untrustworthy
an unreliable friend
an unreliable source of funding
an unreliable car
unreliability noun
the unreliability of the data
a person with a reputation for unreliability
unreliably adverb
a method that works unreliably

Examples of unreliable in a Sentence

Recent Examples on the Web
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.
Snow and cold conditions have become increasingly unreliable. Laura Paddison, CNN Money, 10 Feb. 2026 Fennell has also dropped the elaborate framing devices that make Brontë’s book, among other things, a feast of unreliable narration. Justin Chang, New Yorker, 9 Feb. 2026 In their request for a rehearing, the nonprofits said their members and communities were unfairly being forced to pay to keep a costly and unreliable plant operating and that the department didn't even comply with the law requiring it to show why this was the best alternative. Matthew Daly, Arkansas Online, 8 Feb. 2026 These improbable captors are an average, often unreliable bunch, at least at first. Bilge Ebiri, Vulture, 5 Feb. 2026 See All Example Sentences for unreliable

Word History

First Known Use

1810, in the meaning defined above

Time Traveler
The first known use of unreliable was in 1810

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Cite this Entry

“Unreliable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreliable. Accessed 14 Feb. 2026.

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