station keeper vs desk sergeant

station keeper and desk sergeant both are nouns.

Word	Noun	Adjective	Verb	Adverb
station keeper	Yes	No	No	No
desk sergeant	Yes	No	No	No

As nouns, station keeper and desk sergeant are synonyms defined as:

station keeper and desk sergeant: the police sergeant on duty in a police station

Other synonyms of station keeper include deskman.

station keeper (noun)	desk sergeant (noun)
the police sergeant on duty in a police station	the police sergeant on duty in a police station