This is a term commonly used in military circles. In a deployed environment, it's when two (or more) people sneak into a concrete bunker to fuck. Since privacy is nearly impossible to find, the only safe place to smash is in the closest bunker. Also, may be referred to as bunker lovin'.
That guy from the motor pool just got back from getting some bunker love. That's the 4th time this week!
by SgtWrecker October 31, 2010