What is “a basilica” in medieval Christianity?

The story behind the answer

In medieval usage, a basilica was a papal honor marking a church of exceptional spiritual or historical significance, often with special privileges in liturgy and pilgrimage. It is not the same as a cathedral, which is defined by housing a bishop’s cathedra (seat). Nor is it simply a martyrium (a shrine built over a martyr’s tomb), though some basilicas include such shrines. The option about a Roman public hall refers to the architectural basilica plan, a building type later adapted for Christian worship, not the ecclesiastical rank.

Context: The Middle Ages recognized four “major” basilicas in Rome—St. John Lateran, St. Peter’s, St. Paul Outside the Walls, and St. Mary Major—which anchored pilgrim routes and Jubilee practices. Basilicas display symbols like the ombrellino and tintinnabulum, signifying their papal ties and special role in Christian devotion.