Green’s Dictionary of Slang

wretch-claat n.

also wretch-claht
[SE wretch + Jam. claat or cloth]

(UK black) a term of abuse.

[UK]R. Hewitt White Talk Black Talk 130: The mixed form of ‘wretch-claht’, combining the insult ‘wretch’ from English with the Jamaican word ‘claht’ (cloth).