Writer Jody Rosen has penned a massive 4300-word reflection on his own first name over at Slate, "The Secret History of the Name Jody," and the piece includes some fascinating info about the military's use of the name.
(Commenters on YouTube have already pointed out that Mr. Rosen has illustrated a video titled "U.S. Army Cadence" with an image of Marines, so don't get too excited that you noticed.)
Rosen didn't learn that his name was military slang until he was 27 years old and a cab driver asked him his name. The Vietnam vet replied:
“Jody?” he said. “You’re a pimp.”
I laughed. “Uh, no, not really.”
“No, no, no—if your name is Jody, you’re a pimp.” The driver looked me over in the rearview mirror. “I can tell, you’ve got some Jody-ness in you.”
The driver then explains: “Jody is the m----------r who’s f-----g your woman while you’re in the service.”
Rosen maintains that Jody was absorbed into military culture during WWII and the guy has his roots in Southern black oral culture as "Joe de Grinder."
If your name is Jody, if you've had a Jody screw up your life or even if you're just up nights worrying about him, the article is worth a read. Or you could just watch this NSFW 2007 video where a Marine sings a heartfelt emo ballad that explains why Jody makes it okay to cheat during deployment.