religious ceremony vs religious ritual

religious ceremony and religious ritual both are nouns.

Word	Noun	Adjective	Verb	Adverb
religious ceremony	Yes	No	No	No
religious ritual	Yes	No	No	No

As nouns, religious ceremony and religious ritual are synonyms defined as:

religious ceremony and religious ritual: a ceremony having religious meaning

religious ceremony (noun)	religious ritual (noun)
a ceremony having religious meaning	a ceremony having religious meaning