Best definition
You Know That, Right?
A phrase that can be added on to the end of a statement to make it sound obvious– implying that

the other person is stupid if they didn’t know the statement.

Frenemy: So, have you kicked him out yet?

Anne: No…?

Frenemy: What are you waiting for? He’ll never change.

Anne: I’m not sure wha–

Frenemy: He’s cheating on you, you know that, right?

Anne: Oh! Uh… yeah… I…I uh totally knew that…*cough cough*