unreliable

• Qualifie une personne ou une chose à qui l'on ne peut pas se fier pour fonctionner de manière stable ou être exacte.

Describes someone or something that cannot be trusted to perform consistently well or to be accurate.

1. Prone to error or deceptionB2formal

   Liable to be incorrect or misleading; not trustworthy in terms of accuracy.

   qui peut être erroné ou trompeur

   • The test results were unreliable due to faulty equipment.
   • Eyewitness accounts can often be unreliable.
   • He dismissed the data as unreliable and outdated.

   Synonymesdeceptiveerroneousfalliblefaultyflawedinaccuratemisleadingundependableuntrustworthy

   Antonymesaccuratecorrectdependablereliabletrustworthytruthful

2. Not dependableB1formal

   Not worthy of being relied upon or trusted to fulfill obligations.

   Non fiable, peu digne de confiance

   • She is an unreliable employee who frequently misses deadlines.
   • The old car has become unreliable and breaks down often.
   • He proved to be an unreliable source of information.

   Synonymesdeceitfuldisloyalfickleinconstantirresponsibletreacherousundependableunfaithfulunpredictableuntrustworthy

   Antonymesdependablefaithfulreliableresponsibletrustworthy

3. Unstable and unpredictableB2formal

   Dangerously unstable and likely to change suddenly, often with negative consequences.

   Instable et imprévisible

   • The ladder was unreliable and wobbled dangerously.
   • The region's power grid is unreliable and prone to blackouts.
   • His mood is unreliable, shifting from calm to angry without warning.

   Synonymescapriciouschangeableerraticficklefluctuatingmercurialunpredictablevolatile

   Antonymesconsistentdependablepredictablestabletrustworthy

4. Lacking responsibilityB2informal

   Not showing a sense of responsibility or accountability for one's actions.

   Peu fiable, manquant de responsabilité

   • He is too unreliable to be left in charge of the project.
   • Her unreliable behavior frustrated the entire team.
   • They called him unreliable after he failed to show up again.

   Synonymescarelessirresponsiblenegligentrecklessthoughtlessundependableuntrustworthy

   Antonymesaccountabledependablereliableresponsibletrustworthy