A perfectly straight shit. Used in context with smell but could be used in context with something going perfectly wrong.
So perfectly shitty it comes out straight. It stinks so bad it's straight log.

My son, Ryan said to the other son, Brenden, "Jeeesus man, that smells like straight log!" after Brenden farted in the car last week.
by DaGoose January 31, 2006
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