Acronym for "Risk Management Nightmare" which is a common title given to any drunken Fraternity guy or Sorority girl. Due to the required insurance for most fraternities and sororities, Risk Management is a high priority and a common topic in the Greek world.
After 20 jello shots and 5 games of beer pong, freshman Billy had become a R.M.N. at the Alpha Beta Gamma house.
Dammit, that Pi Chi chick always drinks too much Jaeger and starts offering BJs to anyone, get that R.M.N. outta here!