"sacrament of the Lord's Supper, the Communion," c.1350, from Gk.
eukharistia "thanksgiving, gratitude," later "the Lord's Supper," from
eukharistos "grateful," from
eu- "well" + stem of
kharizesthai "show favor," from
kharis "favor, grace," from PIE base
*gher- "to like, want" (see
horatory).
Eukharisteo is the usual verb for "thank" in the Septuagint and N.T.