dyspnea vs SOB

dyspnea and SOB both are nouns.

Word	Noun	Adjective	Verb	Adverb
dyspnea	Yes	No	No	No
SOB	Yes	No	No	No

As nouns, SOB is a hyponym of dyspnea; that is, SOB is a word with a more specific, narrower meaning than dyspnea:

Other hyponyms of dyspnea include orthopnea, breathlessness, shortness of breath.

dyspnea (noun)	SOB (noun)
difficult or labored respiration	insulting terms of address for people who are stupid or irritating or ridiculous
	a dyspneic condition