viscountess

noun
  1. 1

    The wife of a viscount.

  2. 2

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

    โ€œBefore his own elevation to an earldom, Disraeli's wife was created Viscountess Beaconsfield by Queen Victoria.โ€

Source: https://en.wiktionary.org/wiki/viscountess