amanuensis [əˌmænyuˈɛnsɪs] n.
1.) One who is employed to take dictation or to copy manuscript (American Heritage Dictionary of the English Language).
Etymology: Latin amanuensis (coined by Suetonius), from the phrase servus a manu, slave at handwriting: a, by + manu, ablative of manus, hand + -ensis, belonging to.
"First and foremost, of course, comes my poor Uncle Jeremy, garrulous and imbecile, shuffling about in his list slippers, and composing, as is his wont, innumerable bad verses. I think I told you when last we met of that trait in his character. It has attained such a pitch that he has an amanuensis, whose sole duty it is to copy down and preserve these effusions. This fellow, whose name is Copperthorne, has become as necessary to the old man as his foolscap or as the 'Universal Rhyming Dictionary'" (The Doings of Raffles Haw and Our Lady of Death, Arthur Conan Doyle, 1892).
(Milton, Munkácsy Mihály, 1878)