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1.
Slang for Tylenol PM - and the similar generic store-brand variations of the same - when used as a recreational drug.

Contains diphenhydramine and acetaminophen - the latter should be avoided. It's *really* bad for you when used in excessive amounts.

I doesn't contain dextromethorphan, so it's not technically a robotrip, but roughly similar.

Nonetheless, you can get high off this stuff. Tastes kinda frosty-minty and strong.
It's blue - it's liquid - and you can buy it in almost any drugstore.

A cheap and legal high - Blue Crack.

It's HELLA dangerous, though, because of the acetaminophen. Try something else!!!
by kire October 23, 2007
 
2.
a strain of marijuana, cross between Blue Dream and Green Crack
"I smoked Blue Crack out of this 6 foot bong the other day and i was baaaaaked"

"Yo dawg pack sumo o' dat Blue Crack shiit"
by alienjiz1990 November 27, 2009
 
3.
1) Someone who acts like someone cool in public but when with friends is completely different.
2)In use to why a person may act strange or random.
1)Girl 1: Yeah, he's actually quite nice when he's not surrounded by people.
Girl 2: Ah, so he's blue crack.

2)Girl 1: AH! Look, there's a singing goat!
Girl 2:........
Girl 1: That crazy goat.
Girl 2: You're so on blue crack.
by angus the superduck March 05, 2005