teller vs functionary

teller and functionary both are nouns.

Word	Noun	Adjective	Verb	Adverb
teller	Yes	No	No	No
functionary	Yes	No	No	No

As nouns, functionary is a hypernym of teller; that is, functionary is a word with a broader meaning than teller:

teller: an official appointed to count the votes (especially in legislative assembly)
functionary: a worker who holds or is invested with an office

Other hypernyms of teller include official.

teller (noun)	functionary (noun)
an employee of a bank who receives and pays out money	a worker who holds or is invested with an office
an official appointed to count the votes (especially in legislative assembly)
someone who tells a story