Noun

The unacknowledged or inappropriate adoption of the customs, practices, ideas, etc. of one people or society by members of another and typically more dominant people or society. 

Though there is criticism for the term, “as we look more closely at the entrenched inequality in the history of cultural exchange, it becomes clear that the term “cultural appropriation” is simply giving a name to the exploitation that has always existed and continues to this day. Cultural appropriation allows people to be rewarded for the heritage and labor of oppressed and marginalized communities, disregards the origins and significance of what is being taken, and embraces the products of a culture while reinforcing or ignoring the prejudice experienced by the people who originated it.” 

Source

Oxford Dictionary, Cultural Appropriation Viewing Guide by PBS