In ancient Greek architecture it was the official building of the basileus archon. In Roman architecture, the court and market hall in the form of a rectangular structure divided by columns for the aisles, with a tribune for the court opposite the entrance. By imitation basilics spread throughout the territory of ancient Rome. In time, the basilica began to be called the largest, representative room in the villas of the Roman aristocracy.
In christian architecture this was a multi-nave church with a central nave higher and wider than the others, see the basilica church.
