Green’s Dictionary of Slang

swash-bucket n.

[SE swash-bucket, a receptacle for household rubbish; orig. dial.]

a slatternly woman.

[UK]W. Holloway Dict. of Provincialisms 168/1: Swash-Bucket, A mean, slatternly wench, whose office is to do all the dirty work about a house.
[UK]Farmer & Henley Sl. and Its Analogues.