Something that you will eventually get and continue to get once you become a Marine. Getting the "big green weenie" may include such fine events as: getting fucked with duty on a particularly important weekend, getting in trouble for some small petty shit while being in garrison, getting stationed at a shithole like 29 Dumps.
The "big" represents the big bad Marine Corps picking on the little guy, the Marine. The "green" represents the true color of the Corps. The "weenie" represents getting fucked over.
LCpl Hooligan: What I got duty again?! Dude Im getting fucked in the ass by the big green weenie!
LCpl Didlysquat: Fa sho.
When you are in the Marine Corps and your boss fucks you over big time, making it feel like you have the Marine Corp's Big Green Weenie right up your ass hole with no anal ease even offered.
Andy: I can't believe we have to work for the fifth Saturday in a row.
JR: I know we are definitey getting reamed with the ol big green weenie again.
Being completely screwed over, taking all sorts of crap, and being made to do rediculous shit.
SSgt: Formation 0430 and you're working this weekend.
Sgt: Well Boys. We're taking the Big Green Weenie. No Lube.
when you get fucked (without lube) until your ass bleeds for a week, by some jackass that is a fuckin retard for not puting your paperwork in on time causing you to get fucked out of a re-enlistment.
Cpl *R* hey man are you going to WTI with us next month? Cpl *J* No I just just got fucked by the"BIG GREEN WEENIE" and have two weeks to check out and find a new job.