valedictory oration vs valediction

valedictory oration and valediction both are nouns.

Word	Noun	Adjective	Verb	Adverb
valedictory oration	Yes	No	No	No
valediction	Yes	No	No	No

As nouns, valedictory oration and valediction are synonyms defined as:

valedictory oration and valediction: a farewell oration (especially one delivered during graduation exercises by an outstanding member of a graduating class)

Other synonyms of valedictory oration include valedictory, valedictory address.

valedictory oration (noun)	valediction (noun)
a farewell oration (especially one delivered during graduation exercises by an outstanding member of a graduating class)	the act of saying farewell
	a farewell oration (especially one delivered during graduation exercises by an outstanding member of a graduating class)