noun
Usage: often capitalized F&L
1.
a. : the wife of the president of the United States or if he has no wife the woman whom he chooses to act as hostess at the White House
b. : the wife or hostess of the chief executive of any other country or jurisdiction
one of the daughters will serve as father's hostess and thus be the new first lady of California — Time
cabinet ministers had gathered … as the … bulletins indicated that the First Lady lay dying — New York Times
2. : the leading woman representative or practitioner of any art or profession
the first lady of French letters
the first lady of the dance