Sentence:  He said it would be good for me, going to Grimsby; my hideous, horrible, sewer-minded, greeneyed <WSD>slimeball</WSD> of a two-faced, felonious bastard of an uncle. 
Meaning of the word marked with <WSD> tags:  A person who is regarded as slimy (that is, sneaky or underhanded) or otherwise undesirable.