/
ˈsakrəm(ə)nt/
n.
   - (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.
 - 
(also the Blessed Sacrament or the Holy Sacrament)
 (in Catholic use) the consecrated elements of the Eucharist, especially the bread or Host.
 - a thing of mysterious or sacred significance; a religious symbol.
 
Etymology
ME: from OFr. sacrement, from L. sacramentum ‘solemn oath’, used in Christian L. as a translation of Gk mustērion ‘mystery’.