Top definition
"Fear Of Not Staying In" - Opposite mindset of FOMO, where you don't have the Fear Of Missing Out, but rather dread having to leave your place to do social things.
"I already confirmed "YES" to be there, but man, does that couch look really inviting. Call it a case of FONSI - I'm seriously conflicted."
by WolfmanChi August 15, 2016