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Showing results for unreliable. Search instead for unreliab.
Definitions

unreliable

[uhn-ri-lahy-uh-buhl] / ˌʌn rɪˈlaɪ ə bəl /
ADJECTIVE
not trustworthy, not true
Synonyms
STRONGEST
capricious deceptive dubious false fickle inaccurate irresponsible treacherous tricky uncertain unsound unstable untrustworthy
STRONG
undependable
WEAK
deceitful delusive disreputable erroneous fake fallible fly-by-night furtive hallucinatory hollow implausible inconstant makeshift meretricious mistaken pretended pseudo questionable sham shifty specious unconvincing underhand underhanded unfaithful unsure untrue vacillating wavering weak
Antonyms
STRONGEST
accurate certain clear constant correct definite dependable faithful forthright frank honest reliable right stable steady strong sure true trustworthy truthful
WEAK
responsible

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.

But polygraphs are unreliable and inadmissible in court, and Hatley maintained her innocence under further questioning.

From Slate • Apr. 6, 2026

While these systems are powerful, they consume large amounts of energy and can still produce unreliable results.

From Science Daily • Apr. 5, 2026

But in many indigenous settlements on the outskirts, roads are potholed, classrooms overcrowded, clinics understaffed, electricity unreliable and residents lack secure land titles.

From BBC • Apr. 3, 2026

Goodwin is also troubled by what he labels “stale pricing,” as marks on some positions have a wide variance and can be conservative or unreliable.

From MarketWatch • Mar. 31, 2026

The story of the fact is a story in which the lowest and most unreliable form of knowledge was magically transformed into the highest and most reliable.

From "The Invention of Science" by David Wootton