airport vs airfield

airport and airfield both are nouns.

Word	Noun	Adjective	Verb	Adverb
airport	Yes	No	No	No
airfield	Yes	No	No	No

As nouns, airfield is a hypernym of airport; that is, airfield is a word with a broader meaning than airport:

airport: an airfield equipped with control tower and hangars as well as accommodations for passengers and cargo
airfield: a place where planes take off and land

Other hypernyms of airport include field, flying field, landing field.

airport (noun)	airfield (noun)
an airfield equipped with control tower and hangars as well as accommodations for passengers and cargo	a place where planes take off and land