shortness of breath vs SOB

shortness of breath and SOB both are nouns.

Word	Noun	Adjective	Verb	Adverb
shortness of breath	Yes	No	No	No
SOB	Yes	No	No	No

As nouns, shortness of breath and SOB are synonyms defined as:

Other synonyms of shortness of breath include breathlessness.

shortness of breath (noun)	SOB (noun)
a dyspneic condition	insulting terms of address for people who are stupid or irritating or ridiculous
	a dyspneic condition