Holy Eucharist vs Lord's Supper

Holy Eucharist and Lord's Supper both are nouns.

Word	Noun	Adjective	Verb	Adverb
Holy Eucharist	Yes	No	No	No
Lord's Supper	Yes	No	No	No

As nouns, Holy Eucharist and Lord's Supper are synonyms defined as:

Holy Eucharist and Lord's Supper: a Christian sacrament commemorating the Last Supper by consecrating bread and wine

Other synonyms of Holy Eucharist include Eucharist, Eucharistic liturgy, Holy Sacrament, Liturgy, sacrament of the Eucharist.

Holy Eucharist (noun)	Lord's Supper (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
	the traditional Passover supper of Jesus with his disciples on the eve of his crucifixion