'Senior' definitions:

Definition of 'senior'

From: WordNet
adjective
Older; higher in rank; longer in length of tenure or service; "senior officer" [ant: junior]
adjective
Used of the fourth and final year in United States high school or college; "the senior prom" [syn: senior(a), fourth-year]
adjective
Advanced in years; (`aged' is pronounced as two syllables); "aged members of the society"; "elderly residents could remember the construction of the first skyscraper"; "senior citizen" [syn: aged, elderly, older, senior]
noun
An undergraduate student during the year preceding graduation
noun
A person who is older than you are [syn: elder, senior]

Definition of 'Senior'

From: GCIDE
  • Senior \Sen"ior\, n.
  • 1. A person who is older than another; one more advanced in life. [1913 Webster]
  • 2. One older in office, or whose entrance upon office was anterior to that of another; one prior in grade. [1913 Webster]
  • 3. An aged person; an older. --Dryden. [1913 Webster]
  • Each village senior paused to scan, And speak the lovely caravan. --Emerson. [1913 Webster]
  • 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. [1913 Webster]

Definition of 'Senior'

From: GCIDE
  • Senior \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. [1913 Webster]
  • 2. Belonging to the final year of the regular course in American colleges, or in professional schools. [1913 Webster]