Fellowship with God (Genesis 18:17-33; Exodus 33:9-11; Numbers 12:7, 8), between Christ and his people (John 14:23), by the Spirit (2 Corinthians 13:14; Philippians 2:1), of believers with one another (Ephesians 4:1-6). The Lord's Supper is so called (1 Corinthians 10:16, 17), because in it there is fellowship between Christ and his disciples, and of the disciples with one another.

Noah Webster's New International Dictionary of the English Language

1. (n.) The act of sharing; community; participation.

2. (n.) Intercourse between two or more persons; esp., intimate association and intercourse implying sympathy and confidence; interchange of thoughts, purposes, etc.; agreement; fellowship; as, the communion of saints.

3. (n.) A body of Christians having one common faith and discipline; as, the Presbyterian communion.

4. (n.) The sacrament of the Eucharist; the celebration of the Lord's supper; the act of partaking of the sacrament; as, to go to communion; to partake of the communion.