Junior (jūny&etilde_;r; 277), a. [L. contr. fr. juvenior, compar. of juvenis young. See Juvenile.]
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1. Less advanced in age than another; younger. Abbreviated Jr.
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&hand_; Junior is applied to distinguish the younger of two persons bearing the same name in the same family, and is opposed to senior or elder. Commonly applied to a son who has the same Christian name as his father.
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2. Lower in standing or in rank, or having entered later into a position or office; as, a junior partner; junior counsel; junior captain; the junior Senator from New York.
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3. Composed of juniors, whether younger or a lower standing; as, the junior class; the junior baseball league; of or pertaining to juniors or to a junior class. See Junior, n., 2.
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4. Belonging to a younger person, or an earlier time of life.
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Our first studies and junior endeavors. Sir T. Browne.
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5. of or relating to the third year of a four-year term; -- used of the third or next to final year in a U. S. high school or college. See junior{2}, n..
Syn. -- third-year.
[WordNet 1.5 +PJC]