One who acts with increasing stupidity and doesn't realise it.

One who is so incredibly stupid and needs more than a clue to get back to reality.
Ben is a total claff. Someone needs to check him. check
by FactRzerO July 03, 2003
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Art is walking down the street playing his ring tones for no reason, he's a grade A claff !!
by A.B housen July 14, 2006
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