unreliable

1 of 2

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
ˌən-ri-ˌlī-ə-ˈbi-lə-tē How to pronounce unreliable (audio)
noun
the unreliability of the data
a person with a reputation for unreliability
unreliably
ˌən-ri-ˈlī-ə-blē How to pronounce unreliable (audio)
adverb
a method that works unreliably

unreliability

2 of 2

noun

un·​reliability ¦ən+ How to pronounce unreliability (audio)
: the quality or state of being unreliable

Examples of unreliable in a Sentence

Recent Examples on the Web
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Adjective
Holmes was willing to put unreliable blood-test results in the hands of patients and, even after that fraud was exposed, Fielder showed us investors still willing to support her efforts to get back into the biotech game. — Maxwell Adler, Vanity Fair, 27 Oct. 2026 Incomplete and unreliable demographic data could distort how trillions of federal dollars are distributed across hundreds of programs such as Medicaid, SNAP, WIC, and Head Start. — Julie Morita, Time, 25 Oct. 2026 California officials say the voter list is unreliable and compliance could disrupt the election. — Kevin Rector, Los Angeles Times, 25 Oct. 2026 That makes checking the model name alone an unreliable way to confirm authenticity. — Kurt Knutsson, FOXNews.com, 23 Oct. 2026 See All Example Sentences for unreliable

Word History

First Known Use

Adjective

1810, in the meaning defined above

Time Traveler
The first known use of unreliable was in 1810

Rhymes for unreliable

See All Rhymes for unreliable

Browse Nearby Words

unreliability
unreliable
unrelievable
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Cite this Entry

“Unreliable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreliable. Accessed 28 Oct. 2026.

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