['sakr?m(?)nt]
¦ noun
1. (in the Christian Church) a religious ceremony or ritual regarded as imparting divine grace, such as baptism, the Eucharist, and (in the Catholic and many Orthodox Churches) penance and the anointing of the sick.
2. (also the Blessed Sacrament or the Holy Sacrament) (in Catholic use) the consecrated elements of the Eucharist, especially the bread or Host.
3. a thing of mysterious or sacred significance; a religious symbol.
Origin
ME: from OFr. sacrement, from L. sacramentum 'solemn oath', used in Christian L. as a translation of Gk musterion 'mystery'.