medical extern vs Dr.

medical extern and Dr. both are nouns.

Word	Noun	Adjective	Verb	Adverb
medical extern	Yes	No	No	No
Dr.	Yes	No	No	No

As nouns, Dr. is a hypernym of medical extern; that is, Dr. is a word with a broader meaning than medical extern:

medical extern: a nonresident doctor or medical student; connected with a hospital but not living there
Dr.: a licensed medical practitioner

Other hypernyms of medical extern include doc, doctor, MD, medico, physician.

medical extern (noun)	Dr. (noun)
a nonresident doctor or medical student; connected with a hospital but not living there	a licensed medical practitioner
	a person who holds Ph.D. degree (or the equivalent) from an academic institution