(a.) Composed of juniors, whether younger or a lower standing; as, the junior class; of or pertaining to juniors or to a junior class. See Junior, n., 2.

(2):

(a.) Lower in standing or in rank; later in office; as, a junior partner; junior counsel; junior captain.

(3):

(n.) A younger person.

(4):

(n.) Hence: One of a lower or later standing; specifically, in American colleges, one in the third year of his course, one in the fourth or final year being designated a senior; in some seminaries, one in the first year, in others, one in the second year, of a three years' course.

(5):

(a.) Less advanced in age than another; younger.

(6):

(n.) Belonging to a younger person, or an earlier time of life.

Bibliography Information
Webster, Noah. Entry for 'Junior'. Noah Webster's American Dictionary. https://www.studylight.org/dictionaries/eng/web/j/junior.html. 1828.

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