fernt
The term used to describe the expression on one's face when you say something to them that they find both puzzling and offensive or untrue at the same time, but without the ability to communicate their disagreement with your statement.  A fernt face expresses disgust without saying so, and in most cases, it is a subconsciously generated face, not like disgustful face is made.  You usually have to point it out to the fernt face maker that they are, in fact, fernting on you.
I told him that investing in that stock wasn't a good idea, but all he could do was look at me with a fernt face.