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.

© [Webster 1913].

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.

© [Webster 1913].

senior (definition)