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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.

The internet blackout has only partially eased, but many services remain unreliable or blocked.

From BBC

Harder to quantify is the diplomatic cost of tariffs, as allies conclude the U.S. is an unreliable economic partner.

From The Wall Street Journal

Even where antivenom is available, it is often too expensive, and storage is difficult because most antivenoms require refrigeration in areas with unreliable electricity.

From BBC

Like the metal leash, "we are protected by an unreliable, thin chain of ethics. And if it's cut off, we will be killed by this technology," said Todo.

From Barron's

Advocates called for Europe to bolster its commercial satellite imagery sector to stand in for unreliable U.S. technology.

From Barron's