Near Death Erection is a Jeffism.
When you almost die, like if you start choking in a restaurant with a beautiful woman, and she has to do the Heimlich maneuver, and her breasts are behind you and feel them flopping around while she's saving your life, you spit out the object you were choking on...you turn around to thank her only to find that there's no space between you...your pants have stretched several inches.