narthex

1. (architecture) A western vestibule leading to the nave in some Christian churches.Examples: "we were in the antechamber, called the narthex, which runs across the front of any Byzantine church [...]."; "One of these was Cardinal Jacopo Stefaneschi, [...] who had now conceived ambitious plans for paintings to decorate the entire narthex, or entrance porch, of Avignon's ancient cathedral."; "“Cinco,” Marco bellowed now, hurrying across the narthex to give him a hearty handshake, which Cinco returned without enthusiasm."