assimilation

n. In acculturation psychology, the term assimilation refers to the pattern of cultural change which arises when a person engages with a new cultural group and potentially adopts its psychological characteristics, while simultaneously reducing the amount of contact with the cultural group of origin and relinquishing its characteristics. The terms assimilation and acculturation are sometimes used synonymously to reflect a cultural shift in psychological characteristics from the culture of origin to those of a new culture, although more recently there is a growing tendency to adopt the terminology proposed by John Berry, in which acculturation refers to the phenomenon of cultural change that occurs as a result of firsthand intercultural interaction, and assimilation refers to a specific pattern of acculturation in which a person adopts the characteristics of a new cultural group and gives up the characteristics of the original cultural group.
Some scholars, particularly those who study immigration patterns, retain the term assimilation to refer to the general phenomenon of participation in a new society. This participation can have different aspects, including economic, behavioral, and linguistic aspects. Acculturation is used specifically to refer to the adoption of cultural characteristics. The term segmented assimilation recognizes that immigrants can be received by different segments of the receiving society, including privileged middle-class or disadvantaged neighborhoods. Depending on the resources available to the immigrants and the dynamics of the receiving society, some will experience upward mobility into the middle-class, mainstream society, and others will experience downward mobility (or stay at the same level).   - KN