toller vs toll agent

toller and toll agent both are nouns.

Word	Noun	Adjective	Verb	Adverb
toller	Yes	No	No	No
toll agent	Yes	No	No	No

As nouns, toller and toll agent are synonyms defined as:

Other synonyms of toller include toll collector, toll taker, tollgatherer, tollkeeper, tollman.

toller (noun)	toll agent (noun)
someone employed to collect tolls	someone employed to collect tolls
a person who rings church bells (as for summoning the congregation)