voice over vs phonation

voice over and phonation both are nouns.

Word	Noun	Adjective	Verb	Adverb
voice over	Yes	No	No	No
phonation	Yes	No	No	No

As nouns, phonation is a hypernym of voice over; that is, phonation is a word with a broader meaning than voice over:

voice over: the voice on an unseen commentator in a film of television program
phonation: the sound made by the vibration of vocal folds modified by the resonance of the vocal tract

Other hypernyms of voice over include vocalisation, vocalism, vocalization, voice, vox.

voice over (noun)	phonation (noun)
the voice on an unseen commentator in a film of television program	the sound made by the vibration of vocal folds modified by the resonance of the vocal tract