H-bomb vs nuclear weapon

H-bomb and nuclear weapon both are nouns.

Word	Noun	Adjective	Verb	Adverb
H-bomb	Yes	No	No	No
nuclear weapon	Yes	No	No	No

As nouns, nuclear weapon is a hypernym of H-bomb; that is, nuclear weapon is a word with a broader meaning than H-bomb:

H-bomb: a nuclear weapon that releases atomic energy by union of light (hydrogen) nuclei at high temperatures to form helium
nuclear weapon: a weapon of mass destruction whose explosive power derives from a nuclear reaction

Other hypernyms of H-bomb include bomb, atomic weapon.

H-bomb (noun)	nuclear weapon (noun)
a nuclear weapon that releases atomic energy by union of light (hydrogen) nuclei at high temperatures to form helium	a weapon of mass destruction whose explosive power derives from a nuclear reaction