Lord's Supper vs Holy Eucharist

Lord's Supper and Holy Eucharist both are nouns.

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

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

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

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

Lord's Supper (noun)	Holy Eucharist (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