basically means tits or boobs but for some reasons the t in "tits" is replaced with a y. However, this word has a bad denotation, if something is "yits" then it is bad.
Was created from people pressing the y key on a phone or computer on accident (bc its right netx to the t key) instead of the t key.
Friend 1: Yooo how does the shotgun do 9 damage this game is yits.
Friend 2: It was created by epic games...what did you expect