If the president is a female, the spouse is sometimes called the first gentleman, though some states with female presidents have not used any title at all.
Depending on the country, the expected duties of a First Lady are hosting during receptions at the Presidential Palace, presiding over several welfare institutions, accompanying her husband in official travels abroad, etc.
Famous First Ladies
See also: First Lady of the United States
First lady is a translation of the Italian Prima donna, the leading lady in an opera, or a pretentious man or woman.