steerer vs sea dog

steerer and sea dog both are nouns.

Word	Noun	Adjective	Verb	Adverb
steerer	Yes	No	No	No
sea dog	Yes	No	No	No

As nouns, sea dog is a hypernym of steerer; that is, sea dog is a word with a broader meaning than steerer:

Other hypernyms of steerer include gob, Jack-tar, Jack, mariner, old salt, seafarer, seaman, tar.

steerer (noun)	sea dog (noun)
a beguiler who leads someone into danger (usually as part of a plot)	a man who serves as a sailor
the person who steers a ship