late 15c., from Middle French ecclésiastique and directly from Late Latin ecclesiasticus, from Greek ekklesiastikos "of the (ancient Athenian) assembly," in late Greek, "of the church," from ekklesiastes "speaker in an assembly or church, preacher," from ekkalein "to call out," from ek "out" (see ex-) + kalein "to call" (from PIE root *kele- (2) "to shout"). As a noun, "one holding an office in the Christian ministry," 1650s; it also was used as a noun in Late Latin.