Definition of "Amen"

Amen¹

proper noun
1. (biblical) Jesus, Son of God, as the authority.
  Quotations
  To the angel of the church of Laodicea, write: These are the words of the Amen, the faithful and true witness, the ruler of God’s creation.
  1973, New Testament (New International Version), Revelation 3:14

Amen²

proper noun
1. A surname.

Amen³

proper noun
1. Alternative form of Amun