The Greek word heteros means another of a different kind, the other of two, or something qualitatively different. It is often distinguished from allos (G243, another of the same kind), though this distinction is not always maintained in later Koine Greek. Paul uses heteros powerfully in Galatians 1 when he warns against accepting 'another gospel' — one that is qualitatively different from the true gospel.
The theological weight of heteros in Paul's warning about 'a different gospel' (Galatians 1:6-7) cannot be overstated. Paul does not say there is 'another gospel' — there is no other gospel at all. Any message that differs from the true gospel of grace is not an alternative gospel but a distortion. This word thus serves as a safeguard for the exclusivity and sufficiency of the gospel of Jesus Christ. Heteros also appears in Paul's discussion of spiritual gifts (1 Cor 12), emphasizing the diversity of gifts given by the same Spirit to the body of Christ. In eschatology, Paul promises that believers will have 'different' (transformed) bodies at the resurrection (1 Cor 15:40).