If you describe a person, machine, or method as unreliable, you mean that you cannot trust them.
Diplomats can be a notoriously unreliable and misleading source of information.
His judgement was unreliable.
He had an unreliable car.
unreliability (ʌnrɪlaɪəbɪlɪti)uncountable noun
...his lateness and unreliability.
More Synonyms of unreliable
unreliable in British English
(ˌʌnrɪˈlaɪəbəl)
adjective
not reliable; untrustworthy
an unreliable witness
Examples of 'unreliable' in a sentence
unreliable
And much of the information is unreliable or just plain wrong.
The Times Literary Supplement (2012)
They warned that the month is notoriously unreliable.
The Sun (2010)
It shows what an unreliable person he is.
The Sun (2007)
The careful historian soon learns that juicy stories often have to be jettisoned when sources prove unreliable.
Times, Sunday Times (2016)
It had come from her and was completely unreliable!
Times, Sunday Times (2009)
The continuing reception of unreliable expert evidence simply defeats that purpose.
Times, Sunday Times (2006)
The cars may have looked good but they were notoriously unreliable and not very durable.
Times, Sunday Times (2008)
He was always great fun but completely unreliable.
The Sun (2014)
If the evidence is unreliable then legal aid should be refused.
The Sun (2014)
Slowly, we find that we are dealing with not one but three unreliable narrators.
Times, Sunday Times (2011)
On top of this, a quarter of employers admit that their assessment methods are unreliable.
Times, Sunday Times (2006)
Humble yet sly, he is quick to identify himself as an unreliable narrator.
Times, Sunday Times (2009)
It was not acted upon as the information was deemed unreliable, a source said.
The Sun (2016)
It's a phantom study that is completely unreliable.
Times, Sunday Times (2007)
Telling these stories is not easy, because much surviving evidence is frustratingly unreliable.
The Times Literary Supplement (2012)
Thereafter, he appeared to be trying too hard to wring something extra out of a poor and often unreliable car.
Times, Sunday Times (2008)
They are transformed into a conviction of being quite generally unreliable, untrustworthy, and insatiable.
Bloom, Carol & Gitter, Andrea (contributor) & Gutwill, Susan (contributor) & Kogel,Laura (contributor) & Zaphiropoulos, Lela (contributor) Eating Problems: A Feminist Psychoanalytic Treatment Model (1994)
Surely it is widely known that lie detectors are completely unreliable quack science, and simply don't work.
Times, Sunday Times (2007)
If the programme were an English literature text, the first question you would ask would be about the unreliable narrator.
Times, Sunday Times (2014)
Lack of investment in infrastructure in some parts of the world, combined with unreliable alternative power sources, means the firm should be in high demand.
Times, Sunday Times (2010)
In other languages
unreliable
British English: unreliable /ˌʌnrɪˈlaɪəbl/ ADJECTIVE
If you describe a person, machine, or method as unreliable, you mean that you cannot trust them to do or provide what you want.
The car was slow and unreliable.
American English: unreliable
Arabic: لا يـُمْكِنُ الاِعْتِمَادُ عَلَيْه
Brazilian Portuguese: não confiável
Chinese: 不可靠的
Croatian: nepouzdan
Czech: nespolehlivý
Danish: upålidelig
Dutch: onbetrouwbaar
European Spanish: informal imprevisible
Finnish: epäluotettava
French: imprévisible
German: unzuverlässig
Greek: αναξιόπιστος
Italian: inaffidabile
Japanese: あてにならない
Korean: 신뢰할 수 없는
Norwegian: upålitelig
Polish: zawodny
European Portuguese: não fiável
Romanian: nesigur
Russian: ненадежный
Latin American Spanish: informal
Swedish: opålitlig
Thai: ไว้ใจไม่ได้
Turkish: güvenilmez
Ukrainian: ненадійний
Vietnamese: không đáng tin cậy
Chinese translation of 'unreliable'
unreliable
(ʌnrɪˈlaɪəbl)
adj
[person, firm]不可信赖(賴)的 (bùkě xìnlài de)
[machine, method]不可靠的 (bù kěkào de)
1 (adjective)
Definition
not able to be trusted or relied on
The figures were unreliable because the sample sizes were too small.
Synonyms
inaccurate
The reports were based on inaccurate information.
unconvincing
He was given the usual unconvincing excuses.
implausible
mistaken
She obviously had a mistaken view.
false
She was a false friend, envious of her lifestyle and her success.
uncertain
Students all over the country are facing an uncertain future.
fake
deceptive
Appearances can be deceptive.
erroneous
The conclusions they have come to are completely erroneous.
unsound
The thinking is muddled and fundamentally unsound.
fallible
They are only human and all too fallible.
specious
The Duke was not convinced by such specious arguments.
delusive
delusive emblems of liberty
Opposites
accurate
,
infallible
2 (adjective)
Definition
not able to be trusted or relied on
She had proved to be an unreliable witness and had lied to police.
Synonyms
undependable
irresponsible
It would be irresponsible to accept unrealistic targets.
untrustworthy
His opponents still say he's a fundamentally untrustworthy figure.
unstable
He was emotionally unstable.
treacherous
The President spoke of the treacherous intentions of the enemy.
disreputable
not conscientious
Opposites
reliable
,
dependable
,
trustworthy
,
responsible
,
stable
,
conscientious
Additional synonyms
in the sense of deceptive
Definition
likely or designed to deceive
Appearances can be deceptive.
Synonyms
misleading,
false,
fake,
mock,
ambiguous,
unreliable,
spurious,
illusory,
specious,
fallacious,
delusive
in the sense of delusive
delusive emblems of liberty
Synonyms
deceptive,
misleading,
spurious,
illusory,
specious,
fallacious,
illusive,
chimerical
in the sense of erroneous
Definition
based on or containing an error or errors
The conclusions they have come to are completely erroneous.
Synonyms
incorrect,
wrong,
mistaken,
false,
flawed,
faulty,
inaccurate,
untrue,
invalid,
unfounded,
spurious,
amiss,
unsound,
wide of the mark,
inexact,
fallacious
Synonyms of 'unreliable'
unreliable
Explore 'unreliable' in the dictionary
Additional synonyms
in the sense of fallible
Definition
(of a person) liable to make mistakes
They are only human and all too fallible.
Synonyms
imperfect,
weak,
uncertain,
ignorant,
mortal,
frail,
erring,
prone to error
in the sense of false
She was a false friend, envious of her lifestyle and her success.
Synonyms
treacherous,
lying,
deceiving,
unreliable,
two-timing (informal),
dishonest,
deceptive,
hypocritical,
unfaithful,
two-faced,
disloyal,
unsound,
deceitful,
faithless,
untrustworthy,
insincere,
double-dealing,
dishonourable,
duplicitous,
mendacious,
perfidious (literary),
treasonable,
traitorous,
inconstant,
delusive,
false-hearted
in the sense of irresponsible
Definition
not showing or done with due care for the consequences of one's actions or attitudes
It would be irresponsible to accept unrealistic targets.
Synonyms
thoughtless,
reckless,
careless,
wild,
unreliable,
giddy,
untrustworthy,
flighty,
ill-considered,
good-for-nothing,
shiftless,
harebrained,
undependable,
harum-scarum,
scatterbrained,
featherbrained
in the sense of mistaken
Definition
arising from error in opinion or judgment
She obviously had a mistaken view.
Synonyms
inaccurate,
false,
inappropriate,
faulty,
unfounded,
erroneous,
unsound,
fallacious
in the sense of specious
Definition
apparently correct or true, but actually wrong or false
The Duke was not convinced by such specious arguments.
Synonyms
fallacious,
misleading,
deceptive,
plausible,
unsound,
sophistic,
sophistical,
casuistic
in the sense of treacherous
Definition
disloyal and untrustworthy
The President spoke of the treacherous intentions of the enemy.
Synonyms
disloyal,
deceitful,
untrustworthy,
duplicitous,
false,
untrue,
unreliable,
unfaithful,
faithless,
double-crossing (informal),
double-dealing,
perfidious (literary),
traitorous,
treasonable,
recreant (archaic)
in the sense of uncertain
Definition
not to be depended upon
Students all over the country are facing an uncertain future.
Synonyms
doubtful,
undetermined,
unpredictable,
insecure,
questionable,
ambiguous,
unreliable,
precarious,
indefinite,
indeterminate,
incalculable,
iffy (informal),
changeable,
indistinct,
chancy (informal),
unforeseeable,
unsettled,
unresolved,
in the balance,
unconfirmed,
up in the air,
unfixed,
conjectural,
sketchy (informal)
in the sense of unconvincing
Definition
(of a reason, argument, etc.) not good enough to convince people that something is true or right
He was given the usual unconvincing excuses.
Synonyms
implausible,
unlikely,
lame,
suspect,
thin,
weak,
dubious,
questionable,
hard to believe,
feeble,
improbable,
flimsy,
fishy (informal),
specious,
cock-and-bull (informal),
unpersuasive
in the sense of unsound
Definition
based on faulty ideas
The thinking is muddled and fundamentally unsound.
Synonyms
flawed,
faulty,
weak,
false,
shaky,
unreliable,
invalid,
defective,
illogical,
erroneous,
specious,
fallacious,
ill-founded
in the sense of unstable
Definition
(of a person) having abrupt changes of mood or behaviour