ostiary vs ticket taker

ostiary and ticket taker both are nouns.

Word	Noun	Adjective	Verb	Adverb
ostiary	Yes	No	No	No
ticket taker	Yes	No	No	No

As nouns, ticket taker is a hyponym of ostiary; that is, ticket taker is a word with a more specific, narrower meaning than ostiary:

ostiary: someone who guards an entrance
ticket taker: someone who is paid to admit only those who have purchased tickets

Other hyponyms of ostiary include commissionaire, night porter, ticket collector.

ostiary (noun)	ticket taker (noun)
someone who guards an entrance	someone who is paid to admit only those who have purchased tickets
the lowest of the minor Holy Orders in the unreformed Western Church but now suppressed by the Roman Catholic Church