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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All such theories, however, have appeared to be unreliable and speculative since any first strikes would have to contend with the risk of an enemy launch on warning as well as sufficient systems surviving for a devastating riposte. Lawrence D. Freedman, Foreign Affairs, 14 Apr. 2025 Some customers worry Crusoe’s cloud system is unreliable. Christopher Helman, Forbes.com, 10 Apr. 2025 Jacobs and Booth argued that hiring David Geier compromises the integrity of the scientific process, erodes public trust, and provides a platform for unreliable information. Beth Mole, ArsTechnica, 9 Apr. 2025 With federal support proving unreliable, Illinois must take action to build a stronger, more resilient local food system. Chicago Tribune, 29 Mar. 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 Apr. 2025.

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