sacrament vs religious ritual

sacrament and religious ritual both are nouns.

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

As nouns, religious ritual is a hypernym of sacrament; that is, religious ritual is a word with a broader meaning than sacrament:

sacrament: a formal religious ceremony conferring a specific grace on those who receive it; the two Protestant ceremonies are baptism and the Lord's Supper; in the Roman Catholic Church and the Eastern Orthodox Church there are seven traditional rites accepted as instituted by Jesus: baptism and confirmation and Holy Eucharist and penance and holy orders and matrimony and extreme unction
religious ritual: a ceremony having religious meaning

Other hypernyms of sacrament include religious ceremony.

sacrament (noun)	religious ritual (noun)
a formal religious ceremony conferring a specific grace on those who receive it; the two Protestant ceremonies are baptism and the Lord's Supper; in the Roman Catholic Church and the Eastern Orthodox Church there are seven traditional rites accepted as instituted by Jesus: baptism and confirmation and Holy Eucharist and penance and holy orders and matrimony and extreme unction	a ceremony having religious meaning