double sniff
a gesture done when you and another person aware of this gesture communicate using the Double sniff method, , to point out something obvious both people noticed but don't want to say it, fearing those around might hear or notice
2 friends are in a room and a 3 person wearing a horrible outfit walks in, friend one notices and gets friend 2's attention with a double sniff, and by this, friend 2 already know's what friend one means..