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
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However, Pennington’s claims are widely regarded as unreliable. Stephanie Nolasco, FOXNews.com, 21 Mar. 2026 Kent echoed these sentiments during an interview on the Tucker Carlson Show, claiming that the decision to launch Operation Epic Fury was based on unreliable information. Washington Examiner Staff, The Washington Examiner, 19 Mar. 2026 In winter, the park is closed, and given Glacier’s remote location, cell service is often unreliable. Madison Dapcevich, Outside, 19 Mar. 2026 In his closing argument, Andrew Cherkasky portrayed Saxon as an unreliable witness who fabricated claims about injuries and unpaid wages after being let go from the project. Nancy Dillon, Rolling Stone, 17 Mar. 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 25 Mar. 2026.

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