officer vs captain

officer and captain both are nouns.

Word	Noun	Adjective	Verb	Adverb
officer	Yes	No	Yes	No
captain	Yes	No	Yes	No

As nouns, captain is a hyponym of officer; that is, captain is a word with a more specific, narrower meaning than officer:

As nouns, captain is a hyponym of officer; that is, captain is a word with a more specific, narrower meaning than officer:

officer: a person authorized to serve in a position of authority on a vessel
captain: an officer who is licensed to command a merchant ship

officer (noun)	captain (noun)
a member of a police force	a dining-room attendant who is in charge of the waiters and the seating of customers
someone who is appointed or elected to an office and who holds a position of trust	the pilot in charge of an airship
any person in the armed services who holds a position of authority or command	the naval officer in command of a military ship
a person authorized to serve in a position of authority on a vessel	an officer who is licensed to command a merchant ship
	a policeman in charge of a precinct
	an officer holding a rank below a major but above a lieutenant
	the leader of a group of people

officer (verb)	captain (verb)
direct or command as an officer	be the captain of a sports team