To sophisticate is to make someone or something less innocent. A sophisticate is also a worldly, cultured person.
The root soph in sophisticate has to do with knowledge, and if a person gets sophisticated, they learn new things, especially about the social world. Parents sophisticate their children by teaching them table manners. Going to college sophisticates many people by exposing them to new ideas and other cultures. After becoming sophisticated, people are less natural and innocent, but more cultured. A sophisticate is also a worldly person. Sophisticates do things like go to the opera and drink fine wine.