I guess my definition would be shorter: A Christian who can shrug his shoulders and say, "I don't know."
I'm a member of the Methodist church. Wesley, the founder, came up with the "Wesleyan Quadrilateral": four sources from which each Christian's beliefs necessarily spring.
Scripture
Tradition
Experience
Reason
I like that, because they're not telling me I have to check my brains in at the door. And you're not going to convert anyone, if their own reason and experience bar that, by beating them over the head with a Bible.
Some of the definition fits me, some...not-so-much. Haha I can't even conform to the non-conformists!