Green’s Dictionary of Slang

covess n.

a woman.

1789		G.Parker Life’s Painter 144: He was well acquainted with the cove and covess.
1812		Vaux Vocab. of the Flash Lang. in McLachlan (1964) 233: covess: the mistress of a house or shop, and used on other occasions, in the same manner as Cove, when applied to a man.
1818		W. Perry London Guide 226: I knew he was sweet, not to say nutty, upon the covess.
1821		‘An Amateur’ Real Life in London I 214: The regular covies paired off with their covesses.
1830		Egan Finish to the Adventures of Tom and Jerry (1889) 245: As soon as the police officers [...] make their appearance, the coves and covesses are compelled to fly.
1840		Flash Mirror 16: You’re a nice cove to another’s covess, ain’t you?
1848		Flash Dict. in Sinks of London Laid Open.