One's facial expression when they have a boner.
It is more to do with the horny aura than with an actual boner. There is a slight smile, glint in the eyes and laid back body with the dick as the controller of all thoughts.
1) Ones who face is in resemblance of a boner
2) A common insult that is very well used in the modern world 3) A person who's face is ugly
4) A random person you see (Since some boners ARE certainly RANDOM)
5) synonym for asshole