An ingress of water around the transducer. It can mean one of 2 things, either that you are trying to sound intelligent and threatening or that shit is about to hit the fan and the world will very likely end. It is everyone's worst nightmare (but nobody really knows what it is).
"Hey babe, you wanna know how to fix an IOWAT, I fix them all the time, blindfolded. " or
"Holy shit, there's water in our transducer. We're all gonna die. I thought IOWAT was just a myth. AAAAAAAAAHHHHHHH!"
by Coombop February 24, 2008
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