Lady, a woman of distinction correlatively to Lord (q.v.), used in a more extensive sense in common parlance correlatively to gentleman. As a title it belongs to peeresses, the wives of peers and of lords by courtesy, the word Lady being in all these cases prefixed to the peerage title. The daughters of dukes, marquises, and earls are by courtesy designated by the title Lady prefixed to their Christian name and surname; a title not lost by marriage with a commoner. 'Lady,' prefixed to their husband's surname, is the usual title of wives of Baronets (q.v.) and knights. See COURTESY TITLES, ADDRESS (FORMS OF).
Lady
Chambers's Encyclopaedia, Volume 6: Humber to Malta, p. 478–479
Source scan(s): p. 0493, p. 0494