One who is only interested in going to church or youth group because it is the cool thing to do within his social circle. When not praising the Lord, Aberchristians are generally fucking or drinking-- being as hypocritical as possible. The prefix "Aber" is derived from the fact that they are generally overprivileged rich kids from East Cobb who exclusively wear Abercrombie and Fitch and are as fake as the ideology behind the brand.
"Did you hear about Nerissa fucking Jordan in the JFBC parking lot after youth group?"
"In his new Navigator? God, I hate Aberchristians."