What is the social-psychological expression for "long-term changes in behavior where attitudes have been affected, opinions modified, or prejudices altered"?

conformity

Explanation:

Conformity in social psychology is a word used to mark long-term changes in someone's behavior, options, and beliefs in relation to others and in order to fit the group.

It can be done under the influence of the peer-pressure or under the imaginary idea of social norms that an individual has.

It shouldn't be confused with adjustment, which is an effort to cope with standards and ideas of the society to be accepted, but that doesn't need to be followed by a permanent change in character.