communion (n.) Look up communion at Dictionary.com
late 14c., from Old French comunion "community, communion" (12c.), from Latin communionem (nominative communio) "fellowship, mutual participation, a sharing," used in Late Latin ecclesiastical language for "participation in the sacrament," from communis "common, general" (see common (adj.)). Used by Augustine, in belief that the word was derived from com- "with, together" + unus "oneness, union."