Spolia: modern name for architectural elements that are reused in a later construction.
Spolia is the Latin word (meaning “loot”) that art historians and archaeologists use to describe architectural elements that are reused in a later construction. Spoliation was quite common in Late Antiquity, although there are many earlier examples, and has been interpreted as evidence for economic decline. While not untrue, there is a symbolic aspect as well. For example, the builders of the Arch of Constantine reused sculpture from the second century CE to present their emperor’s reign as a return to the age of Trajan, Hadrian, and Marcus Aurelius. The use of columns from pagan temples in Christian churches was to prove that the old gods were powerless.