station agent vs stationmaster

station agent and stationmaster both are nouns.

Word	Noun	Adjective	Verb	Adverb
station agent	Yes	No	No	No
stationmaster	Yes	No	No	No

As nouns, station agent and stationmaster are synonyms defined as:

station agent and stationmaster: the person in charge of a railway station

station agent (noun)	stationmaster (noun)
the person in charge of a railway station	the person in charge of a railway station