1) Bookkeeper, at times 2) Computer keyboardist 3) Computer typesetter 4) Data analyst, at times 5) Incoming one 6) Keyboard user, often 7) Ledger keeper 8) Logger without an ax 9) New member 10) One coming onstage 11) One matriculating 12) One on the way in 13) One providing input 14) One who came in 
• (n.) One who makes an entrance or beginning.
En'ter·er noun One who makes an entrance or beginning. A. Seward.