GP vs doctor

GP and doctor both are nouns.

Word	Noun	Adjective	Verb	Adverb
GP	Yes	No	No	No
doctor	Yes	No	Yes	No

As nouns, doctor is a hypernym of GP; that is, doctor is a word with a broader meaning than GP:

Other hypernyms of GP include doc, Dr., MD, medico, physician.

GP (noun)	doctor (noun)
a physician who is not a specialist but treats all illnesses	children take the roles of physician or patient or nurse and pretend they are at the physician's office
	a licensed medical practitioner
	a person who holds Ph.D. degree (or the equivalent) from an academic institution

GP (verb)	doctor (verb)
	give medical treatment to
	alter and make impure, as with the intention to deceive
	restore by replacing a part or putting together what is torn or broken