valedictory

(noun) a farewell oration (especially one delivered during graduation exercises by an outstanding member of a graduating class). Synonyms: valediction, valedictory address, valedictory oration.

(adj) of or relating to an occasion or expression of farewell. Examples: "A valedictory address." "Valedictory praise for his uniformly manly course." "A suitable valedictory gesture."

(adj) of a speech expressing leave-taking. Example: "A valedictory address."