From Middle English Cristien, from Old French chrestien, from Latin Chrīstiānus, from Ancient Greek Χρῑστιᾱνός (Khrīstiānós), from Χρῑστός (Khrīstós, “Christ, anointed [one]”) + Latin suffix -ānus. The older form is Christen. Doublet of cretin. By surface analysis, Christ + -ian.