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
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

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.
Weldon has also shared unreliable claims about reproductive health. — Chantelle Lee, TIME, 12 Mar. 2025 In a press briefing, the NTSB shared the investigation's initial findings on potential unreliable data recording and an Air Traffic Control communications issue that led to the crash. — Kathleen Wong, USA TODAY, 11 Mar. 2025 Poor-quality or biased data leads to unreliable AI models. — Aditi Godbole, Forbes, 10 Mar. 2025 No one likes dealing with unreliable internet, and at $39.99 for one router (or $99.99 for three), these Eero Wi-Fi deals are an easy way to upgrade your home network without overspending. — Juhi Wadia, PCMAG, 10 Mar. 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

Rhymes for unreliable

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Browse Nearby Words

unreliable
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Cite this Entry

“Unreliable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreliable. Accessed 22 Mar. 2025.

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Thesaurus: All synonyms and antonyms for unreliable

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