I am guessing you mean the word for self,even, own,actual etc "Fein" as in "Sinn Fein".

It would be pronounced as either Fayne or Fane. unless it referred to myself "Me Fein" then it would be pronounced Ma Hayne. I can't do accents on this keyboard.

There is a similar word " Fiann" as in "Fianna Fail" then the pronounciation would be "Feeann"

Hope this helps

Slan