general practitioner vs doc

general practitioner and doc both are nouns.

Word	Noun	Adjective	Verb	Adverb
general practitioner	Yes	No	No	No
doc	Yes	No	No	No

As nouns, doc is a hypernym of general practitioner; that is, doc is a word with a broader meaning than general practitioner:

general practitioner: a physician who is not a specialist but treats all illnesses
doc: a licensed medical practitioner

Other hypernyms of general practitioner include doctor, Dr., MD, medico, physician.

general practitioner (noun)	doc (noun)
a physician who is not a specialist but treats all illnesses	a licensed medical practitioner