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Showing results for unreliable. Search instead for unreliabl.
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

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

As for working out one's geographic position, though, Chris Shaw, co-founder and chief executive of Advanced Navigation, says his firm's tech can use alternatives when GPS proves unavailable or unreliable.

From BBC • Mar. 9, 2026

The accused has blood on his clothes, but he is a butcher; the testimony is explicit, but the witness is unreliable.

From "The Invention of Science" by David Wootton