Basilica: A basilica is a large rectangular building with multiple sections including a transept. It serves as both public gathering places and religious spaces.
Nave: The nave is the central part of a basilica where people sit or stand during religious services. It runs from the entrance to where it intersects with the transept.
Crossing: The crossing refers to the area where the nave and transept intersect in a basilica. It often holds significant architectural features or decorative elements.