Because the festival of Epiphany is part of the church year and developed as the Christian church grew, you will not find the word “epiphany” in the Bible. I did think it was important to include it, however, because many churches still celebrate Epiphany as part of the church calendar.
It is celebrated on January 6 and the twelve days starting on December 25 and ending on January 5 have been call “The Twelve Days of Christmas.” In Western Christianity January 6 has always celebrated the appearance of Jesus to the Gentiles, or non-Jewish people. This appearance is represented by the coming of the Wise Men to see the baby Jesus as told in Matthew 2:1-12.
In Eastern Christianity Epiphany is a celebration of the baptism of Jesus. This story, told in Mark 1:9-11 tells about the appearance of Jesus to all of humanity as the Son of God.