النَّسْخُ وَالِانْتِحَالُ
Copying another’s composition and passing it off as one’s own.
Naskh emphasizes reproduction of an existing expression, whereas intihal adds the element of adopting or claiming another's composition. Together they refer to a serious kind of borrowing in which both the words and their attribution are taken over.
An openly attributed quotation differs because the original author is not concealed.