The Collaborative International Dictionary of English v.0.48:

Teller \Tell"er\, n.
   1. One who tells, relates, or communicates; an informer,
      narrator, or describer.
      [1913 Webster]

   2. One of four officers of the English Exchequer, formerly
      appointed to receive moneys due to the king and to pay
      moneys payable by the king. --Cowell.
      [1913 Webster]

   3. An employee of a bank who receives money paid in, and pays
      money out, and makes records of such transactions.
      [1913 Webster +PJC]

   4. One who is appointed to count the votes given in a
      legislative body, public meeting, assembly, etc.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Teller
    n 1: United States physicist (born in Hungary) who worked on the
         first atom bomb and the first hydrogen bomb (1908-2003)
         [syn: Teller, Edward Teller]
    2: an official appointed to count the votes (especially in
       legislative assembly) [syn: teller, vote counter]
    3: an employee of a bank who receives and pays out money [syn:
       teller, cashier, bank clerk]
    4: someone who tells a story [syn: narrator, storyteller,
       teller]