Insetic

1. A person lacking certain knowledge that another group/community of people do know.

2. Someone that doesn’t understand an inside joke.

Person 1: Hey do you remember that time in history class when the teacher had a breakdown?
Person 2: Yeah I remember! “No more crackers!”
Person 1: Hahaha, that was so crazy.
Person 3: Why is that so funny guys, I don’t get it
Person 2: Wow dude, you’re such an insetic.

INSET day

A day off school in England which is mainly used for sleeping and eating or seeing friends
Its used for teacher training

Girl 1: OMG its an INSET day on friday!! lets go shopping!!
Girl 2: OMG yes!!!!