Answer: usr

AnswerCrossword Clue
USRAmerican militia: Abbr.
USRBranch of armed forces.
USRSoldiers in the news: Abbr.
USRMilitary group.
USRGuard unit: Abbr.
USRMilitary initials
USRMilitary standby group: Abbr.
USRRelative of R.O.T.C.
USRKin of R.O.T.C.