the "christians" as word formed later for the followers of Christ
it's not the only word that formed this way
we use the word Ιωαννίτες for the Knights of Saint John (Ιωάννης) http://en.wikipedia.org/wiki/Knights_Hospitaller
when the word formed used with 2 ways
Χριστιανός and Χρηστιανός
to be honest I read this in a heretic nover I have read these days but I found that iit also in this article
from a priest.
the χρηστιανός word means honorable, fair, αγαθός (can't find the english word) and ethic.
the Χριστιανός word is from the word χριστός which means κεχρισμένος< ο φέρων το χρίσμα < αρχ. ελλ. ρήμα: χρίω
and I really can't translate it but I hope that someone else can so I write it.