To express one's opinion. The word is similar to conversate. Speakers who use conversate tend to also use opinionate.
That bitch was starting to opinionate about how much she don't like my clothes in front of the other girls at the party until I told her to shut the fuck up.
to pinch off an opinion on someone. its verbal scat.
if your Boo wants to be in your bizness she should get the fuck in it or don't opinionate!