Meaning that you have an erection at the present time or talking about one in the past. The 'Shtonk' being the erection an the 'on' meaning you have it, so a Shtonk off would of course mean you dont have one.

v. collectively or individually finding someone/something to blame for a problem, as opposed to brainstorming which connotes finding solutions to a problem

n. the act of finding someone/something to blame for a problem

(from a TV ad for HD television)