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Related to unreliability: conferred, ameliorating, pay heed, reconfirm, give rise to


Marked by or exhibiting a lack of reliability.

un′re·li′a·bil′i·ty, un′re·li′a·ble·ness n.
un′re·li′a·bly adv.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˌʌnrɪlaɪəˈbɪlətɪ) or


the condition of being not reliable or untrustworthy
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014




  1. (I found the almond trees as) dependable as the swallows of Capistrano, announcing another spring —Wallace Stegner
  2. As reliable as the day following the night —Dorothea Straus
  3. [A collection of art works] as spotty as a Dalmation and not half as beautiful —Manuela Hoelterhoff, on the new Wallace wing at the Metropolitan Museum of Art, Wall Street Journal, March 17, 1987
  4. Consistent and productive as machines —Gay Gaer Luce
  5. Dealing with Owen Roe was like walking across a bog. You never knew when the ground might give way under your feet —Julia O’Faolain
  6. Dependable as a floating crap game —Harry Prince
  7. Dependable as clockwork … —Anon
  8. Dependable as daylight —Beryl Markham
  9. A duty dodged is like a debt unpaid; it is only deferred, and we must come back and settle the account at last —Joseph Fort
  10. Duty without responsibility is like pomp without power —Edward, Duke of Windsor
  11. Fickle as a changeful dream —Sir Walter Scott
  12. It [buying a house] was like joining a church because it committed me to spending every weekend I could get … to working on the place —George V. Higgins
  13. (You’ve got) no more responsibility than a one-eyed jack rabbit —Elmer Kelton
  14. Reliability’s like a string we can only see the middle of —William McFee
  15. (About as) reliable as a Pravda editorial —Joseph Wambaugh
  16. Reliable as a salary —Frank R. Stockton
  17. Reliable as crystal balls, goat innards, and prayer —Harold Adams
  18. Reliable as he was eccentric —Mark Twain
  19. Reliable as reading tea leaves or the bumps on one’s head —Peter J. Bonacich, letter to editor of Discover, April, 1986
  20. Responsibility rested upon him as lightly as the freckles on his nose —Alice Caldwell Hegan
  21. Solid as tombstones —Helen Hudson
  22. Wore, like a garment, an air of wholesome reliability —Mazo De La Roche
  23. Would always be there … like some familiar landmark —Barbara Pym, The Sweet Dove Died
Similes Dictionary, 1st Edition. © 1988 The Gale Group, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.Unreliability - the trait of not being dependable or reliableunreliability - the trait of not being dependable or reliable
irresponsibility, irresponsibleness - a form of untrustworthiness; the trait of lacking a sense of responsibility and not feeling accountable for your actions
instability - unreliability attributable to being unstable
irreproducibility - the quality of being unreproducible; "he could not explain the irreproducibility of the results of his experiment"
fallibility - the likelihood of making errors
dependability, dependableness, reliability, reliableness - the quality of being dependable or reliable
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


[ˈʌnrɪˌlaɪəˈbɪlɪtɪ] Nfalta f de fiabilidad
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


[ˌʌnrɪlaɪəˈbɪləti] n
[person] → manque m de sérieux
[confession, testimony, evidence] → manque m de fiabilité
[clock, instrument, car] → manque m de fiabilité
Collins English/French Electronic Resource. © HarperCollins Publishers 2005


Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


[ˌʌnrɪlaɪəˈbɪlɪtɪ] nscarsa affidabilità
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995
References in classic literature ?
He noted with surprise the absence of Taglat, whom he had expected to find awaiting him outside the tent of Achmet Zek; but, accustomed as he was to the unreliability of apes, he gave no serious attention to the present defection of his surly companion.
At the first landing you run up against a pail and a broom, whereupon "mother" expatiates upon the unreliability of servant-girls, and bawls over the balusters for Sarah to come and take them away at once.
Tired of the unreliability of the under-25s, she's moving towards the older gent.
Tape drive failures, faulty tape media, and incomplete or corrupt backups all contribute to the unreliability of tape backups.
Daley claimed the voice was Stone's but Stone's legal team say there is no evidence to support the claims, arguing that Daley's evidence should have been excluded or that the jury should have been given a firmer warning about the testimony's possible unreliability.
The throwaway comment in its text that the boys could equally well be posing for photographs as soldiers leaves the viewer stranded between black humor and the unreliability of reportage.
The purpose of this paper is to illustrate how displaying disattenuated correlation coefficients along with their unadjusted counterparts will allow the reader to assess the impact of unreliability on each bivariate relationship.
The judges ruled on Tuesday that Stone's appeal "must succeed" on the basis of the unreliability of key prosecution witness Barry Thompson, who gave evidence at Stone's trial claiming he had confessed to the killings in prison.
So too, Peter Lang's reputation for unreliability as a scholarly publisher cannot be improved by its careless work in producing this volume.
Likewise, they rated the boar-eating tribe as having qualities they previously had linked with boars, including irritability, excitability, unreliability, short life, fast movement, good running ability, aggressiveness and brown eyes.
Such is the unreliability of what serial killers say, even confessions to unsolved crimes, without independent corroboration, must be treated with caution,