during the act of defecation, as stool leaves the body flush simultaneously to suck the stool down in one fluid motion to expose maximum smell control

When you're being horny (especially around friends) and as a result shame ensues.

Verb;

Shooting the Gap refers to when one has the beegees and is sitting on the toilet releasing a massive amount of watery feces then suddenly they have to barf so they must "shoot the gap" between their privates and the bowl.