Blank expression
From Wikipedia, the free encyclopedia
A blank expression is a facial expression characterized by the neutral position of facial features and implies a lack of strong emotion. It may be caused by a lack of emotion, boredom, slight confusion (such as when someone refers to something which the listener does not understand) a deliberate attempt to disguise one's emotions, such as when playing poker, or a sign of depression. It is also the expression most common while asleep.
In poker, this expression is referred to as a "poker-face" (shortened to a po-face). In poker one does not want others to know if one is holding a good or bad hand, hence the need for a blank expression.