In old time comics there was a great thing where, when a character gives a dirty look the cartoonist would draw knives, or daggers, coming out of their eyes, pointing at where they are looking. Urbandictionary.com defines it this way:

When someone who tries to intimidate another person, they will flinch quickly towards that person, and exercise a quick widening of the eyes, in effort to scare away the supposed moron who tried to intimidate them in the first place. Usually, the kid who gives the dagger eyes is much more adapted to survive through mockery, and this action helps to scare off possible douche bags who try to scare the dagger eyed kid.
In Hawaii they call it “stink-eye”. With all the stabbings, “dagger eyes” worked for me.