IPA: /ɪnˈkɒnvɪnsəbl/
KK: /ɪnˈkɒnvɪnsəbl/
Not able to be persuaded or convinced about something.
She was inconvincible about her beliefs, no matter what evidence was presented.
Inconvincible → It is formed from "in-" (meaning not) and "convincere" (meaning to conquer or overcome). The word describes something that cannot be overcome or conquered, hence, not convincible.
Think of 'not' ('in-') being able to 'overcome' ('convincere') something — that's why inconvincible means something that cannot be overcome.