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 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
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Ousmane Dembele has been transformed from a talented but unreliable and injury-prone winger into a Ballon d’Or-winning striker. Nick Miller, New York Times, 30 May 2026 Normal logistics break down — transportation, fuel or banking become unreliable. Christopher Elliott, Forbes.com, 30 May 2026 One of the biggest challenges fashion brands face today is unreliable supply chains and inventory management to accurately meet customer demand and expectations. Fairchild Studio, Footwear News, 28 May 2026 Yet students still encounter empty dispensers and unreliable access to products in school bathrooms, raising concerns that the DOE still lacks a reliable implementation and distribution process to ensure students can consistently access products. Gale Brewer, New York Daily News, 28 May 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

Browse Nearby Words

Cite this Entry

“Unreliable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreliable. Accessed 31 May. 2026.

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