valedictory (adj) - saying farewell; of or pertaining to an occasion of leave-taking [val-i-dik-tuh-ree]
BREAKDOWN: VALE- (farewell) + DICT- (speak) + -ORY (relating to)
a valedictory can be a ceremonial farewell speech or a farewell ceremony like a graduation
a valedictorian—usually the student with the highest academic distinction in the class—gives the valedictory address at a commencement exercise
See also: vindictive
“Don't be dismayed at good-byes. A farewell is necessary before you can meet again. And meeting again, after moments or lifetimes, is certain for those who are friends.” ―Richard Bach