old salt vs officer

old salt and officer both are nouns.

Word	Noun	Adjective	Verb	Adverb
old salt	Yes	No	No	No
officer	Yes	No	Yes	No

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

old salt: a man who serves as a sailor
officer: a person authorized to serve in a position of authority on a vessel

old salt (noun)	officer (noun)
a man who serves as a sailor	a member of a police force
	someone who is appointed or elected to an office and who holds a position of trust
	any person in the armed services who holds a position of authority or command
	a person authorized to serve in a position of authority on a vessel

old salt (verb)	officer (verb)
	direct or command as an officer