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 Hamas is regarded as an unreliable partner, a Sunni Muslim Brotherhood group that fits uneasily within the largely Shiite pro-Iranian alliance. Hussein Ibish, The Atlantic, 27 Apr. 2024 Despite increases in rental car demand, Hertz said it’s been bruised by its fleet of electric vehicles—made up primarily of Teslas—that are unreliable and more costly than their gas-guzzling counterparts. Sasha Rogelberg, Fortune, 25 Apr. 2024 See all Example Sentences for unreliable 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'unreliable.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1810, in the meaning defined above

Time Traveler
The first known use of unreliable was in 1810

Dictionary Entries Near unreliable

Cite this Entry

“Unreliable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreliable. Accessed 4 May. 2024.

Last Updated: - Updated example sentences
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