IPA: //ʌn.pəˈsweɪ.sɪv//
KK: /ʌnˈpɜr.sweɪ.sɪv/
Not able to convince someone or make them believe something.
The speaker's arguments were unpersuasive, and the audience remained unconvinced.
Unpersuasive → It is formed from "un-" (meaning not) and "persuasive" (from Latin "persuadere", meaning to convince or persuade). The word "unpersuasive" means not able to convince or lacking the ability to persuade.
Think of 'not' ('un-') being added to 'persuade' — this helps you remember that 'unpersuasive' means something that does not convince.