1. Sac·ra·ment
   Eccles. a visible sign of an inward grace, esp. one of the solemn Christian rites considered to have been instituted by Jesus Christ to symbolize or confer grace: the sacraments of the Protestant churches are baptism and the Lord's Supper; the sacraments of the Roman Catholic and Greek Orthodox churches are baptism, confirmation, the Eucharist, matrimony, penance, holy orders, and extreme unction.
2. Sac·ra·ment
   (often cap.) Also called"Holy Sacrament."the Eucharist or Lord's Supper.
3. Sac·ra·ment
   the consecrated elements of the Eucharist, esp. the bread.
4. Sac·ra·ment
   something regarded as possessing a sacred character or mysterious significance.

This definition is in context to Religion. See more contextual defintions for Sacrament (N.).