def1.Girls in a friend group who act like they practically live together and cant ever be separated and have seen the worst of each other;since they arent actuly sisters they call themselfs shisters def2.A veiwer of James Charles
a stupid thing many basic white girls say. if you say "shister", you are basic, and trying desperately to be cool. shister is like the female version of bro, but more cringey.