Very fast occurring and unexpected penis erection which can disappear as quickly as it has appeared.
She: What the hell is that?
He: Never mind, it is just a blitzboner.
She: What does this mean *laughing*
He: It is a boner which occurs and disappears as quick as a lightning bolt.
She: Ah, I see now....errr....wait...I see nothing. Where is it now?
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.