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.
The cooling system in her second-story apartment in Albuquerque, New Mexico, had always been unreliable. Ignacio Calderon, USA Today, 21 May 2025 This showed that changes in the truck's speed produced turbulence in the liquid helium, making measurements of its presence unreliable. John Timmer, ArsTechnica, 19 May 2025 To counter this risk, the Kremlin has accelerated its efforts to transition to a new model of political and social control and replace the most unreliable segments of the political and business elite with loyalists personally tied to Putin. Andrei Yakovlev, Foreign Affairs, 16 May 2025 Special teams are often overlooked, but the Sun Devils had unreliable field goal kickers last season, which makes the addition of Gomez, who hit 20 of 25 attempts in 2024, significant. Antonio Morales, New York Times, 16 May 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

Browse Nearby Words

Cite this Entry

“Unreliable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreliable. Accessed 27 May. 2025.

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