Our new 'Word Of The Day' article update : slimeball , n :
(biology) A round lump made up of or coated with slime or a slime-like substance such as mucus. (helminthology, specifically) A mucus-coated lump containing the cercariae (“parasitic larvae”) of a liver fluke (of the phylum Platyhelminthes). (originally US, colloquial, derogatory) A person who is regarded as slimy (that is, sneaky or underhanded) or otherwise undesirable.