Concept in Christianity whereby, as an adult, one chooses to follow a Christian life, sometimes requiring a baptism or re-baptism. Due to the enthusiasm and comittment often displayed by people who have chosen to be "born again" it is often negatively associated with the more evangenical and "bible-thumping" type of Christian.
On Separation Sunday, "born again" seems to refer both to the Christian concept and also act as a literal pun about resurrection. A major theme throughout the album. However, Holly's resurrection and when she is "born again" are to seperate events that take place at different points in her life.
See Also: high as hell