more advanced than another in age; prior in age; elder; hence, more advanced in dignity, rank, or office; superior; as, senior member; senior counsel.-belonging to the final year of the regular course in american colleges, or in professional schools.-a person who is older than another; one more advanced in life.-one older in office, or whose entrance upon office was anterior to that of another; one prior in grade.-an aged person; an older.-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.