Here is a sampling of uses of Koinonia in the New Testament:

Fellowship with the Son, 1 Cor. 1:9
Fellowship/Fellow-feeling with the Spirit, 2 Cor. 13:14, Phil. 2:1
Connection to the poor, sign of fellowship, Rom. 15:26
Right hand of fellowship, Gal. 2:9
Taking part in relief, sharing, 2 Cor. 8:4, 2 Cor. 9:13
Close relationship to blood and body of Christ, 1 Cor. 16:10
Participation in the faith, Phlm. 6
All things in common association, Acts 2:44