MISTRESS n. 2 definitions
A title of courtesy formerly prefixed to the name of a woman, married or unmarried, but now superseded by the contracted forms, Mrs., for a married, and Miss, for an unmarried, woman. Now Mistress Gilpin (careful soul). Cowper.
NARTHEX n.
The portico in front of ancient churches; sometimes, the atrium or outer court surrounded by ambulatories; -- used, generally, for any vestibule, lobby, or outer porch, leading to the nave of a church.