You wondered if Epiphany is a word of Greek derivation.  Yes, from
Greek Epiphaneia.

I studied with a Greek Orthodox priest when I was trying to find a
church.  This Greek church in Seattle celebrated Christmas on January
6, at the same time as Epiphany, in the old tradition.   I was never
converted to Greek Orthodox because my husband was not a Christian at
that time, a requirement in that church.

I love the Greek language, and learned to pidgin-speak Modern Greek
from my Greek roommate, and her friends, in college.  I could sing in
Greek and they said I had no accent, rare for a western person.  And I
could read the street signs when my husband and I went to Greece many
years later, although I'd lost the ability to read Greek at anything
but a rudimentary level.  I am wild about Greek.

Mariel