A rough-and-tumble Marine Corps woman. A female, grizzled, warfighter. Her manliness is often attributed to her clit being as large as a man's penis.
Big-clitty Marine Corps GF (noun) - A masculine female Marine Corps woman.
"I saw the sergeant talking with that Marine officer again. I bet he wants to make her his Big-clitty Marine Corps GF."
"I've seen her dude, she's a beast. Definitely could make a great Big-clitty Marine Corps GF.