Green’s Dictionary of Slang

slummock n.

[slummock v.]

a slovenly person, thus slummocky, slovenly.

[US]Flash (NY) 3 Oct. n.p.: [She] altogether had the manner and appearance that is quaintly described as ‘slummyky’.
[US]Whip & Satirist of NY & Brooklyn (NY) 14 Jan. n.p.: the whip wants to know If slummiky Liz has made her man flog anyone yet.
[US]M.G. Hayden ‘Terms Of Disparagement’ in DN IV:iii 203: slummock, a dirty, untidy woman. ‘What can you expect of a girl with a slummock for a mother!’.
[UK]J. Cary Horse’s Mouth (1948) 48: He thought [...] his step-mother a slummock who would rather flop about in a wrapper listening to Wag-ner or Bee-thoven than wash her face or darn his socks.