Not Being Funny. A state of sincerity, where you're so illiterate that the only way you can express how sincere you are is by highlighting how insincere you aren't. In acronym form for efficiency purposes, to be used largely in written communication i.e. msn, text, email, law exam
"nbf, but if i don't get into university heads will roll."
"nbf, but just because you like anal sex doesn't mean you need to tell everyone."