I have come across many sites on the tamil slang.
‘Kasmaalam’ is a word used in tamil. I am not sure of the meaning of the word. But for sure it is used in an abusing sense. In many tamil movies this word is spoken as a madras slang. There are many words used in tamil slang that are meaningless. But I think this word has taken its origin from the Sanskrit word ‘kashmalam’ which means dirty, disgraceful or foul. There are many tamilians who are anti- Sanskrit have accepted to use the Sanskrit word at least as a jargon. (albeit unknowingly)