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.
The 5,000 sailors and Marines on board have been working sustained combat operations, dealing with extension after extension and unreliable access to food, basic hygiene supplies, and mail. — Andrea N. Goldstein, The Atlantic, 28 Aug. 2026 Print editions overseas also reach service members in remote locations where internet access is spotty and unreliable. — Jacob Rosen, CBS News, 27 Aug. 2026 Cell service was unreliable, and text messages could take hours to reach the other end. — Kurt Knutsson, FOXNews.com, 26 Aug. 2026 Savio is the only player to appear on both lists, embodying the unreliable nature of transfer valuations. — Conor O'Neill, New York Times, 26 Aug. 2026 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

See All Rhymes for unreliable

Browse Nearby Words

unreliability
unreliable
unrelievable
See all Nearby Words

Cite this Entry

“Unreliable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreliable. Accessed 1 Sep. 2026.

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