This occurs in classrooms or other large public settings. Usually one person begins to cough, and other people who needed to cough, but were afraid to do so, join in, causing multiple coughing sounds at the same time.
Person 1: Ugh why does everyone have to cough at once, it's so annoying.
Drunk-bff. Drunk best friend forever. The phenomenon that occurs when two people are best friends when drunk, however when sober, they have nothing to say to each other. They might even find each other completely boring when sober.
Me and john are dbff's, we have so much fun at parties, but it's so awkward to be around him when we're sober.
I really want to talk to her right now, but we're only dbffs.