declamation vs oratory

declamation and oratory both are nouns.

Word	Noun	Adjective	Verb	Adverb
declamation	Yes	No	No	No
oratory	Yes	No	No	No

As nouns, oratory is a hypernym of declamation; that is, oratory is a word with a broader meaning than declamation:

declamation: vehement oratory
oratory: addressing an audience formally (usually a long and rhetorical address and often pompous)

declamation (noun)	oratory (noun)
vehement oratory	addressing an audience formally (usually a long and rhetorical address and often pompous)
recitation of a speech from memory with studied gestures and intonation as an exercise in elocution or rhetoric