look up any word, like ratchet:
 
1.
An annoying person who hovers over you on a train, bus, or on a plane, and constantly coughs and/or sneezes on you. "Level 5" refers to the highest level of biohazard in a "hot lab".
I'm trying to stay away from the walking Level 5s on the train, because I have no sick time left at my job.
by pentozali November 08, 2005