Used often by Marines, as a noun, in reference to individuals that do not meet Marine Corp standards. Generally in reference to physical fitness or appearance.
"'If any of you nasties set off one of these in the dark . . ." Keeping Faith, John Schaeffer and Frank Schaeffer, Carroll and Graf distributed by publishers group west.
"...that is of course if you nasties have what it takes to become part of my beloved Marine Corps. Get some!" mavericmarine, http://www.leatherneck.com/forums/showthread.php?t=33597&page=3
"If you hated the Marine Corps until you got your $30 grand, then all of a sudden you were a motivator, you will eventually fade back into the realm of nasties." warrior0369, http://www.militarytimes.com/forums/showthread.php?t=1559730