oceanaut vs skilled worker

oceanaut and skilled worker both are nouns.

Word	Noun	Adjective	Verb	Adverb
oceanaut	Yes	No	No	No
skilled worker	Yes	No	No	No

As nouns, skilled worker is a hypernym of oceanaut; that is, skilled worker is a word with a broader meaning than oceanaut:

oceanaut: a skilled worker who can live in underwater installations and participate in scientific research
skilled worker: a worker who has acquired special skills

Other hypernyms of oceanaut include skilled workman, trained worker.

oceanaut (noun)	skilled worker (noun)
a skilled worker who can live in underwater installations and participate in scientific research	a worker who has acquired special skills