housewife vs viscountess

housewife

noun
  • The wife of a householder; the mistress of a family; the female head of a household. 

  • A woman whose main employment is homemaking, maintaining the upkeep of her home and tending to household affairs; often, such a woman whose sole [unpaid] employment is homemaking. 

  • A little case or bag for materials used in sewing, and for other articles of female work. 

viscountess

noun
  • The wife of a viscount. 

  • A woman holding the rank of viscount in her own right. 

How often have the words housewife and viscountess occurred in a corpus of books? (source: Google Ngram Viewer )