Easton's Bible Dictionary: M. G. Easton, M.A., D.D.

Fulness

1. Of time (Gal. 4:4), the time appointed by God, and foretold by the prophets, when Messiah should appear.
2. Of Christ (Jn. 1:16), the superabundance of grace with which he was filled.
3. Of the Godhead bodily dwelling in Christ (Col. 2:9), i.e., the whole nature and attributes of God are in Christ.
4. Eph. 1:23, the church as the fulness of Christ, i.e., the church makes Christ a complete and perfect head.