valedictory

Definitions:

A farewell address.
- Nuttall's Standard dictionary of the English language. By Nuttall, P.Austin. Published 1914. (noun) (n.) (noun)
An oration or address delivered on bidding farewell.
- Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874. (noun) (n.) (noun)
Bidding farewell.
- Nuttall's Standard dictionary of the English language. By Nuttall, P.Austin. Published 1914. (adjective) (adj.) (adjective)
Saying farewell: farewell: taking leave.
- The american dictionary of the english language. By Daniel Lyons. Published 1899. (adjective) (adj.) (adjective)
Farewell.
- The Winston Simplified Dictionary. By William Dodge Lewis, Edgar Arthur Singer. Published 1919. (interjection) (interj.) (interjection)
A farewell speech, especially a farewell address at a school or college commencement.
- The Winston Simplified Dictionary. By William Dodge Lewis, Edgar Arthur Singer. Published 1919. (noun) (n.) (noun)

Usage examples:

You were chosen to deliver the valedictory because you can make a speech so much better than I. What is the use of bringing up this subject now, just a few minutes before our commencement begins?
- Madge Morton's Victory by Amy D.V. Chalmers
Thurlow and Colman did not even acknowledge their copies, and were lashed for their breach of friendship with rather more vigour than the Moral Satires display, in The Valedictory which unluckily survived for posthumous publication, when the culprits had made their peace.
- Cowper by Goldwin Smith
He was mentioned in Sir John French's valedictory despatch.
- The Irish at the Front by Michael MacDonagh