The proper term is "post-Christian". Most of the civilized world has already wandered over to that paradigm, where you're going to church XMas and Easter, and putting up Xmas trees. Rather than defining your belief system in terms of abortion or gay marriage, you see it as a social construct.
It's a natural progression from fundamentalism through the spectrum of secularism to arrive at post-Christianity. You might abandon some core principles along the way, like the virgin birth, or going to hell if your wife sucks your you-know-what, but the Xmas trees are still cool.