More often than not, it is used in a derogatory manner. Can also be a term of endearment. Personally I mostly say it when someone tells me they did something I have no interest in.
Negative
"This is my first definition on Urban Dictionary!"
"Sick ass fool...."

Positive
"Dood I just got a keg!"
"SICK ASS FOOL!"
by slompythepirate July 3, 2013
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Anybody named Nick who sells 1 gram cartridges of "wax" but it's really vape juice for 45 to dumb lil niggas and beat them up when they want their money back.
"Oh shit you know Nick"
"Hell yeah! He's a SICK ASS FOOL"
by imasickassfoo August 31, 2018
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