Basilica - Oxford Definition

[From the Greek basilik, ‘royal’] a church with aisles and a nave higher than the aisles. The nave was usually lit by the windows of a clerestory. Such churches first came into being in the Early Christian era and were modelled on Roman basilicas (large meeting places or halls of justice). With its longtitudinal axis, usually terminating with an apse at one end of the nave, the basilica plan was later adapted for Romanesque and Gothic cathedrals.