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Synonyms

unreliable

American  
[uhn-ri-lahy-uh-buhl] / ˌʌn rɪˈlaɪ ə bəl /

adjective

  1. not reliable; not to be relied or depended on.

    Synonyms:
    untrustworthy, irresponsible, undependable

unreliable British  
/ ˌʌnrɪˈlaɪəbəl /

adjective

  1. not reliable; untrustworthy

    an unreliable witness

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • unreliability noun
  • unreliableness noun
  • unreliably adverb

Etymology

Origin of unreliable

First recorded in 1830–40; un- 1 + reliable

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Mays called “Amadeus” a “memory play,” noting that “every aspect of this production is exploring that — it’s all filtered through the warped, distorted memories and imaginings of its unreliable narrator.”

From Los Angeles Times

Some free servers might work occasionally, but it’s unreliable at best.

From Salon

Headline lap times in testing are notoriously unreliable as indicators of form as the specification in which the cars are running is not made public.

From BBC

Resorting to facial recognition and other technologies addresses the reality that self-reported age has proven unreliable, with minors routinely lying about their birthdates to circumvent platform safety measures.

From Barron's

“But this technology can be highly unreliable, and it can cause harm.”

From Salon