un·​re·​li·​able | \ˌən-ri-ˈlī-ə-bəl \

Definition of unreliable 

: not reliable : undependable, untrustworthy an unreliable friend an unreliable source of funding an unreliable car

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Other Words from unreliable

unreliability \ˌən-​ri-​ˌlī-​ə-​ˈbi-​lə-​tē \ noun
the unreliability of the data a person with a reputation for unreliability
unreliably \ˌən-​ri-​ˈlī-​ə-​blē \ adverb
a method that works unreliably

Examples of unreliable in a Sentence

Recent Examples on the Web

Alibaba’s reporting is based on gross merchandise value (or GMV), which Bloomberg argues is an unreliable metric that doesn’t seem to correlate with revenue. Jon Porter, The Verge, "Alibaba’s Singles Day sales dwarf Amazon’s biggest day," 12 Nov. 2018 The unreliable updates have been a cause for concern since shortly after Windows 10's release. Peter Bright, Ars Technica, "Microsoft’s problem isn’t how often it updates Windows—it’s how it develops it," 20 Oct. 2018 Local officials in some far-flung municipalities dispute that figure, and say that some mountain communities are still struggling with an unreliable grid. NBC News, "U.S. plans to remove backup power generators in Puerto Rico. Officials worry it's hurricane season.," 11 July 2018 The situation, while not an all-time-worst data breach, was a frustrating reminder of the unreliable state of security on corporate networks. Lily Hay Newman, WIRED, "The Worst Cybersecurity Breaches of 2018 So Far," 9 July 2018 Predicting the money picture for coming years is an unreliable exercise. Milwaukee, Milwaukee Journal Sentinel, "Borsuk: New MPS leader's first moves are crowd pleasers. Will they lead to lasting results?," 25 May 2018 Time and again, the President has proven himself an unreliable partner. Philip Elliott, Time, "President Trump Spiked an Immigration Compromise He Supported," 15 June 2018 Ironically, the Wi-Fi at the Federal Communications Commission, the agency that regulates the airwaves, was totally unreliable until a few years ago. New York Times, "In Washington, a Brighter Spotlight on Technology," 9 May 2018 Some foreign policy experts said that canceling the Iran deal could send a message to Kim's regime that the United States is an unreliable negotiating partner. Author: Karen Deyoung, Anne Gearan, David Nakamura, Anchorage Daily News, "Trump expected dump Iran nuclear deal," 8 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unreliable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of unreliable

1810, in the meaning defined above

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Last Updated

24 Nov 2018

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Time Traveler for unreliable

The first known use of unreliable was in 1810

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More Definitions for unreliable


un·​re·​li·​able | \ˌən-ri-ˈlī-ə-bəl\

Kids Definition of unreliable

: not worthy of trust He got rid of his unreliable car.

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More from Merriam-Webster on unreliable

Spanish Central: Translation of unreliable

Nglish: Translation of unreliable for Spanish Speakers

Britannica English: Translation of unreliable for Arabic Speakers

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having a pattern of small flowers

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