Holy Eucharist vs Holy Sacrament

Holy Eucharist and Holy Sacrament both are nouns.

Word	Noun	Adjective	Verb	Adverb
Holy Eucharist	Yes	No	No	No
Holy Sacrament	Yes	No	No	No

As nouns, Holy Eucharist and Holy Sacrament are synonyms defined as:

Holy Eucharist and Holy Sacrament: a Christian sacrament commemorating the Last Supper by consecrating bread and wine

Other synonyms of Holy Eucharist include Eucharist, Eucharistic liturgy, Liturgy, Lord's Supper, sacrament of the Eucharist.

Holy Eucharist (noun)	Holy Sacrament (noun)
a Christian sacrament commemorating the Last Supper by consecrating bread and wine	a Christian sacrament commemorating the Last Supper by consecrating bread and wine