SEAL vs navy man

SEAL and navy man both are nouns.

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

As nouns, navy man is a hypernym of SEAL; that is, navy man is a word with a broader meaning than SEAL:

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

Other hypernyms of SEAL include bluejacket, sailor, sailor boy.

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