Any situation considered negative in some manner, or will more often than not have a less than ideal result. Awkward situations also apply.
Eric: Today, I was almost got caught smoking weed by my parents.
Peter: Man, that is heat business...

Jeff: I just saw my brother kissing my sister...
Brett: Wow, that is absolute heatest of business.
by Kowlessari June 3, 2011
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