The title of Mrs.
We use the terms every day, without thinking anything of them, but Mr. and Mrs (aka Mister and Mistress) have not always been the standard term of address we take for granted today. Many would be surprised at the derivation of the words. Derived from the Old French 'mestier' (modern French 'métier') meaning 'craft or trade'; from the Latin 'ministerium' meaning 'office'.
Chambers: n. (fem. of master) A woman employer of servants, or head of a house or family; a woman having power of ownership; a woman teacher; a woman will skilled in anything; a woman loved and courted; a concubine; vocatively, madam