lieutenant junior grade(n = noun.person) lieutenant jg - an officer holding a commissioned rank in the United States Navy or United States Coast Guard; below lieutenant and above ensign;
is a kind of commissioned naval officer

first grade, first lieutenant, grade, grade crossing, grade insignia, grade point, grade point average, grade school, grade separation, junior, junior class, junior college, junior featherweight, junior high, junior high school, junior lightweight, junior middleweight, junior school, junior status, junior varsity, junior welterweight, lieutenant, lieutenant colonel, lieutenant commander, lieutenant general, lieutenant governor, lieutenant jg, low grade, make the grade, police lieutenant, second lieutenant