Invurp
An awkward biological phenomena that occurs where an individual produces a big enough yawn that air enters too quickly down the throat, making a "burp-like" sound.
Jane: "dude, were you the one that burped in class?"
John: "No! I swear to god I invurped! You know...an inverse burp"
John: "No! I swear to god I invurped! You know...an inverse burp"