Meaning

noun United States physicist (born in Hungary) who worked on the first atom bomb and the first hydrogen bomb (1908-2003)

noun an official appointed to count the votes (especially in legislative assembly)

noun an employee of a bank who receives and pays out money

originFrom Middle English tellere (“one who counts or enumerates; one who recounts or relates; teller”), equivalent to tell (verb) + -er.

Etymology from Wiktionary, CC BY-SA 3.0