\Sen"ior\, a. [L. senior, compar. of senex, gen. senis,
old. See {Sir}.]
1. More advanced than another in age; prior in age; elder;
   hence, more advanced in dignity, rank, or office;
   superior; as, senior member; senior counsel.
2. Belonging to the final year of the regular course in
   American colleges, or in professional schools.

\Sen"ior\, n.
1. A person who is older than another; one more advanced in
   life.
2. One older in office, or whose entrance upon office was
   anterior to that of another; one prior in grade.
3. An aged person; an older. --Dryden.
         Each village senior paused to scan, And speak the
         lovely caravan.                       --Emerson.
4. One in the fourth or final year of his collegiate course
   at an American college; -- originally called {senior
   sophister}; also, one in the last year of the course at a
   professional schools or at a seminary.