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
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.
Ride-sharing services like Uber and taxis are abundant in Palma, but become unreliable at the farther reaches of the island. Emilio Parra Doiztua, New York Times, 16 Oct. 2025 Despite the novel’s use of the unreliable female narrator trope, Stone wanted to avoid that altogether. Maureen Lee Lenker, Entertainment Weekly, 11 Oct. 2025 The rest of the reservation is connected to the grid, but the power is unreliable and outages can sometimes last days. Nate Perez, NPR, 7 Oct. 2025 This variability makes tungsten diselenide unreliable for quantum applications. Neetika Walter, Interesting Engineering, 3 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 17 Oct. 2025.

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