|1.||Fourth point of contact|
Airborne military term for your ass. The five points of contact for landing after a parachute jump are (in order), 1. balls of feet, 2. heels of feet, 3. thighs, 4. ass, and 5. shoulder blades.
Term usually used to describe one who needs to pull their heads out of their ass.
"Ssg. Harston hasn't put my leave request in yet."
"Well, he better pull his head out of his fourth point of contact and get cracking on that!"