un·​re·​li·​able | \ ˌən-ri-ˈlī-ə-bəl How to pronounce unreliable (audio) \

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 How to pronounce unreliability (audio) \ noun
the unreliability of the data a person with a reputation for unreliability
unreliably \ ˌən-​ri-​ˈlī-​ə-​blē How to pronounce unreliably (audio) \ adverb
a method that works unreliably

Examples of unreliable in a Sentence

Recent Examples on the Web

Awkward loops and unreliable magnetic connections are no match for the jumble of the everyday backpack or bag. Melissa Riofrio, PCWorld, "Dell's Inspiron 7000 2-in-1 Black Edition laptops save you from lost pens and hot panels," 8 Jan. 2019 We were freed from using the geriatric, unreliable oven that came with our apartment, and cookies, pizzas, and baked chicken dishes were now heated all the way through. Megan Geuss, Ars Technica, "Review: The June oven made me want a camera in every cooking device," 22 Dec. 2018 According to a 2011 study by the Justice Department, 94 to 98 percent of burglar alarms were false, making the systems unreliable. Paul Sullivan, New York Times, "Can Artificial Intelligence Keep Your Home Secure?," 29 June 2018 And is Taylor taking advantage of a program by basing his identity on DNA results that some experts consider unreliable? Christine Willmsen, The Seattle Times, "Lynnwood man tried to use a home DNA test to qualify as a minority business owner. He was denied — now he’s suing.," 13 Sep. 2018 Very unreliable, plays outside the scheme, not reliable in coverage, his eyes are all over the place. Albert Breer, SI.com, "How a Soldier’s Story Helped Dan Quinn Build the Falcons," 2 July 2018 In the international arena, Turkey has become a major actor in the Syrian war, a crucial player in the attempts to curb the European migration crisis and an unreliable ally to the United States and in the North Atlantic Treaty Organization. New York Times, "Turkey’s Election: What to Watch For," 24 June 2018 The tests were found to be unreliable, and the company was forced to void or revise thousands of test results over accuracy concerns. Catherine Ho, SFChronicle.com, "Theranos CEO Elizabeth Holmes indicted for alleged wire fraud," 15 June 2018 MacLean’s lawyers have attacked the DNA evidence as tainted and unreliable, but less than two months ago a different jury needed only 45 minutes to convict MacLean in the babysitter case. Marc Freeman, Sun-Sentinel.com, "'Superthief' back on trial in 1977 Boca rape; 'I was scared to death,' victim testifies," 12 June 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

3 Mar 2019

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Time Traveler for unreliable

The first known use of unreliable was in 1810

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English Language Learners Definition of unreliable

: not able to be trusted to do or provide what is needed or promised
: not believable or trustworthy


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

Comments on unreliable

What made you want to look up unreliable? Please tell us where you read or heard it (including the quote, if possible).


to corrupt or become corrupted

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