1. not able to make someone believe that something is true or real; not persuasive

Examples

• His excuse for being late was completely unconvincing.
• The actor’s performance was unconvincing and wooden.
• She gave an unconvincing smile when asked about her plans.
• The witness provided unconvincing testimony during the trial.
• The company’s explanation for the price increase seemed unconvincing.
• His unconvincing argument failed to sway the jury.
• The politician’s promises sounded unconvincing to most voters.