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.
Some say the deal will amount to nothing if the money isn’t used to fix longstanding problems like unreliable public services. — Gonzalo Zegarra, CNN Money, 3 Sep. 2026 This reality just creates more unreliable confusion for the end consumer. — Nirav Tolia, Fortune, 3 Sep. 2026 Some online estimates, which Cancian dismissed as unreliable, put the military cost at more than a hundred billion dollars. — John Cassidy, New Yorker, 31 Aug. 2026 The fix always seems to require better opinions, and opinions are exactly the thing that’s unreliable in the first place. — Rhett Power, Forbes.com, 30 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 5 Sep. 2026.

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