If you describe someone as opinionated, you mean that they have very strong opinions and refuse to accept that they may be wrong. Sue is the extrovert in the family; opinionated, talkative and passionate about politics.
What is an opinionated person?
If you are opinionated, you obstinately hold on to your opinions, and you don't hesitate to let other people know what those opinions are. Opinionated is based on the word "opinion," which itself comes from the Latin word opinari, meaning to think.
Is being an opinionated person a bad thing?
Being opinionated certainly has it's downside risks. Some types of opinionated people come off as arrogant, abrasive, or can end up lacking tact and hurting themselves in their careers.