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.
Consumers are increasingly turning to cyberspace for guidance about health and medicine, yet a growing number of sites offer unreliable information, new research shows. Aj Willingham, AJC.com, 28 Apr. 2026 In recent months, women have begun sharing stories of similar relationship problems, often during outdoor activities, often with unreliable male partners who use the circumstances to leave their partners behind, sometimes for good. Susan Young, PEOPLE, 28 Apr. 2026 Renewable energy is neither unreliable nor unaffordable. Voice Of The People, New York Daily News, 27 Apr. 2026 But what about unreliable heroes? John Hopewell, Variety, 27 Apr. 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 5 May. 2026.

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