Sick nasty is used to describe a situation, person, or thing so disgusting and gross that it deserves to be called both sick and nasty. Sick nasty can be used in almost all context, I mean what isn't sick nasty?

(orgin the celtic swim '06-07 team)
Wow that shirt is really sick nasty. I just wanted to gouge my eyes out today when I saw Brett because he is so sick nasty. etc
by Celtic Swim '06-07 January 28, 2007
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When something is super awesome/cool/tight/sexy... etc

since two negatives makes a positive (sick- bad, nasty- bad= good)
That board is sick-nasty.

Everything that dosn't involve __________, is sick-nasty.

Your mom is sick nasty.
by reveingiallo March 5, 2008
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to explain something of importance.
to be amused of another thing.
by Alex =) June 17, 2006
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when someone says 'the sick-nasty' it usually means that they're refuring to sex.
did you and john do the sick-nasty yet? haha.
by klepto420 November 4, 2007
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Contrary to its wording. Sick-Nasty is a good thing. It means that something is so cool that it is sick but at the same time nasty because you want some of it.
Kevins girlfriend is sick because she acts just like a guy, but then nasty because we want to f*#$k her, therefore making her Sick-Nasty.
by Pulchunk September 5, 2006
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Although this phrase sounds derogatory, it is in fact a very, very positive thing. It is used the same way as "cool," or "awesome" in modern language.
Guy: "That nollie mctwist backflip was sick nasty disgusting!"
by Ugly Dude Guy May 24, 2008
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When something is so fucking awesome that it is at the same time dope sick AND nasty.
"Dude did you see that crazy trick i just did?"
"Yeah man, that was dope sick nasty!"
by Jovomo March 6, 2010
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