navy man vs Navy SEAL

navy man and Navy SEAL both are nouns.

Word	Noun	Adjective	Verb	Adverb
navy man	Yes	No	No	No
Navy SEAL	Yes	No	No	No

As nouns, Navy SEAL is a hyponym of navy man; that is, Navy SEAL is a word with a more specific, narrower meaning than navy man:

navy man: a serviceman in the navy
Navy SEAL: a member of a Naval Special Warfare unit who is trained for unconventional warfare

Other hyponyms of navy man include coastguardsman, SEAL, striker, submariner.

navy man (noun)	Navy SEAL (noun)
a serviceman in the navy	a member of a Naval Special Warfare unit who is trained for unconventional warfare