Maundy vs ceremonial

Maundy and ceremonial both are nouns.

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

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

Maundy: a public ceremony on Maundy Thursday when the monarch distributes Maundy money
ceremonial: a formal event performed on a special occasion

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

Maundy (noun)	ceremonial (noun)
a public ceremony on Maundy Thursday when the monarch distributes Maundy money	a formal event performed on a special occasion

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