poostachio
When you can smell "poo" but can't tell where the heck the stench is coming from. Often associated with a animal or toddler's inherent ability to stash their poo which leads to a game of "What's that smell?" or "What died in here?"
I've searched everywhere and even gone through three cans of fabreeze but still can't find the source of the stench in this house...we've got ourselves a poostachio!