A soldier, marine, pilot, or sailor that goes to war as a means to satisfy his/her 'addicition' to the exhilaration/adrenaline rush/strong bond with other soldiers/ killing of the world's criminals/ etc. experienced during war, be it good or bad.
' Yo, man, whyz George going back to Afghanistan, his 8 year contracts up, aint it?'
' Yea, cuz, but hes goign back cause he a war junkie, mang. He gets a high out of shooting mofos, and getting shot back at. he loves the bond between him and the other dudes he fighting with. theyre all that matterz out therez in da battlefield, mang.'