Shot Cock Violation
When a man uses a urinal in a restroom but is unable to release his urine with the customary dick reveal due to stage fright. After standing pee-less for 10-15 seconds a man will sometimes discharge saliva from his mouth to encourage his urine to follow suit and discharge. This pee-less stand at the urinal is known as a "shot cock violation" since it causes a reservation of the urinal for a non-pee activity.
Brian had held in his urine throughout the whole movie in order to not miss any scenes. He limped to he men's restroom where he found three pee-less men hogging the three urinals. After waiting 15 seconds and not hearing any streams of urine hitting the cakes, Brian yelled out "shot cock violation" and one of the men hung his head in shame and slowly backed away from the urinal exposing it for use while is pee-less cock also hung it's head in shame.