unreliable

adjective

un·​re·​li·​able ˌən-ri-ˈlī-ə-bəl How to pronounce unreliable (audio)
: 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
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Some suspect that the idea proposed by Maslov and Shpinel really belonged to their professor, Fritz Lange, but was signed by Maslov because, as a member of the Communist Party, he was trusted by the authorities more than the unreliable German émigré. Literary Hub, 23 Oct. 2025 Defense lawyers did not call any witnesses and said that the core of the case, military statements taken over 50 years ago, were manifestly unreliable, with no independent supporting evidence offered to back the prosecution case. CNN Money, 23 Oct. 2025 It's been a consistently reliable genre in the decades since, pairing mental anguish and unreliable perspectives with nightmarish imagery and terrors that lie just beyond our perceptions. Steven Thrash, Entertainment Weekly, 19 Oct. 2025 The casting of Goth in dual roles as both Victor’s mother and Elizabeth further contributes to the unreliable narration. Clayton Davis, Variety, 17 Oct. 2025 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 24 Oct. 2025.

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