A fork of Rural Dictionary
1) Whats USMS, its like a pile of dog crap, no one knows where it came from or how it got there but when you see it, all you know is its a load of shit
2) United States Mystery Service, or, United States Made-up Service
"LCDR Reagan, wait, wasn't he a gunnery sergeant in the marines?" "Yea, but he joined USMS and anything's possible there"