The Latin word basilica (derived from Greek, Basiliké Stoà, Royal Stoa), was originally used to describe a Roman public building (as in Greece, mainly a tribunal), usually located at the center of a Roman town (forum). In Hellenistic cities, public basilicas appeared in the 2nd century BC.

After the Roman Empire became officially Christian, the term came by extension to refer to a large and important church that has been given special ceremonial rites by the Pope. Thus the word retains two senses today, one architectural and the other ecclesiastical.