ticket taker vs door guard

ticket taker and door guard both are nouns.

Word	Noun	Adjective	Verb	Adverb
ticket taker	Yes	No	No	No
door guard	Yes	No	No	No

As nouns, door guard is a hypernym of ticket taker; that is, door guard is a word with a broader meaning than ticket taker:

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

Other hypernyms of ticket taker include doorkeeper, doorman, gatekeeper, hall porter, ostiary, porter.

ticket taker (noun)	door guard (noun)
someone who is paid to admit only those who have purchased tickets	someone who guards an entrance