mistressship

Century Dictionary and Cyclopedia

1. n. Rule or dominion of one who is mistress; authority exercised by a woman.
2. n. Ladyship: a style of address, preceded by a possessive pronoun: as, your mistress-ship.

Wiktionary

1. n. obsolete Female rule or dominion.
2. n. obsolete ladyship; a style of address, used with the personal pronoun.

GNU Webster's 1913

1. n. Female rule or dominion.
2. n. obsolete Ladyship, a style of address; -- with the personal pronoun.