extern vs physician

extern and physician both are nouns.

Word	Noun	Adjective	Verb	Adverb
extern	Yes	No	No	No
physician	Yes	No	No	No

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

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

Other hypernyms of extern include doc, doctor, Dr., MD, medico.

extern (noun)	physician (noun)
a nonresident doctor or medical student; connected with a hospital but not living there	a licensed medical practitioner