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.
Designed to be compact and portable, HyDee is targeted at outdoor, industrial, and emergency applications, including scenarios where access to the electrical grid is unreliable or nonexistent. Neetika Walter, Interesting Engineering, 10 Jan. 2026 One of the main themes this season, certainly the second half of the season, is Amy having to contend with unreliable narrators around her past. Joshua Rothkopf, Los Angeles Times, 9 Jan. 2026 And Anna is an unreliable narrator. Ben Travers, IndieWire, 8 Jan. 2026 In the letter, Jaworski and the finance leaders warned aldermen their proposals to cut and add revenue were based on unreliable numbers. Jake Sheridan, Chicago Tribune, 7 Jan. 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 Jan. 2026.

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