formality vs ceremonial

formality and ceremonial both are nouns.

Word	Noun	Adjective	Verb	Adverb
formality	Yes	No	No	No
ceremonial	Yes	Yes	No	No

As nouns, ceremonial is a hypernym of formality; that is, ceremonial is a word with a broader meaning than formality:

Other hypernyms of formality include ceremonial occasion, ceremony, observance.

formality (noun)	ceremonial (noun)
compliance with formal rules	a formal event performed on a special occasion
a manner that strictly observes all forms and ceremonies
a requirement of etiquette or custom

formality (adjective)	ceremonial (adjective)
	marked by pomp or ceremony or formality