Crossword clues for the word: USR The word USR has appeared as an answer to at least 8 crossword clues on different crossword puzzles. Crossword clues for USR Showing 1 to 8 of 8 results Clue(s) American militia: Abbr. Branch of armed forces. Guard unit: Abbr. Kin of R.O.T.C. Military initials Military standby group: Abbr. Relative of R.O.T.C. Soldiers in the news: Abbr.