Term used in the Marines to refer to the gossip passed around by those of a lower rank (usually lance corporals) about deployments, promotions, and any other topic pertaining to a unit's agenda.
Lance Corporal: So, I heard through the Lance Corporal Underground that we are going to Okinawa in May.
Other Lance Corporal: STFU I'm peeing.
Other Lance Corporal: STFU I'm peeing.
by jmusmc85 June 6, 2010