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 Democrats have historically panned Bolton as an unreliable narrator who made faulty claims about U.S. intelligence in the run-up to the war in Iraq. W. James Antle Iii, Washington Examiner, "Democrats wield Bolton book as shield against Trump 'Beijing Biden' attacks," 19 June 2020 Economists say that data might be unreliable, though. Ryan Randazzo, azcentral, "Arizona unemployment rate dropped sharply in May, though economists advise caution on figures," 18 June 2020 Civil rights groups that campaign on surveillance and facial recognition say that would be concerning because the technology is unreliable and expands police powers—effects that burden communities of color most of all. Tom Simonite, Wired, "A Bill in Congress Would Limit Uses of Facial Recognition," 12 June 2020 The police then labeled him as an unreliable and inconsistent witness and classified him as a person of no interest. Fox News, "Sweden ends decades-long probe into 1986 assassination of PM Olof Palme," 11 June 2020 But then that study was also found to be unreliable, and The Lancet issued a retraction. Jeva Lange, TheWeek, "The misdirected ire at WHO," 10 June 2020 The police then labelled Engstrom as a unreliable and inconsistent witness and classified him as a person of no interest. Time, "Sweden Drops Investigation Into Unsolved 1986 Murder of Prime Minister Olof Palme," 10 June 2020 Many economists discount the ADP figures—based on the payroll company’s customer records—as an unreliable predictor of the government’s jobs report, typically coming two days later. Olivia Rockeman, Fortune, "What is the real unemployment rate? Your questions about that shocking jobs report, answered," 9 June 2020 Indonesia is rushing to normalize based on unreliable data, risking inflaming the outbreak, said Hidayana. Grace Sihombing, Bloomberg.com, "Virus Deaths May Be Three Times Official Tally in Indonesia," 7 June 2020

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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Time Traveler for unreliable

Time Traveler

The first known use of unreliable was in 1810

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Statistics for unreliable

Last Updated

22 Jun 2020

Cite this Entry

“Unreliable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreliable. Accessed 3 Jul. 2020.

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More Definitions for unreliable


How to pronounce unreliable (audio)

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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