amanuensis (n.)

"one who takes dictation or copies what is written by another," 1610s, from Latin amanuensis "adjective used as a noun," an alteration of (servus) a manu "secretary," literally "servant from the hand;" from a for ab "from, of," here used as a designation of office (see ab-), + manu, ablative of manus "hand" (from PIE root *man- (2) "hand"). With -ensis, for which see -ese.