applied science vs subject area

applied science and subject area both are nouns.

Word	Noun	Adjective	Verb	Adverb
applied science	Yes	No	No	No
subject area	Yes	No	No	No

As nouns, subject area is a hypernym of applied science; that is, subject area is a word with a broader meaning than applied science:

applied science: the discipline dealing with the art or science of applying scientific knowledge to practical problems
subject area: a branch of knowledge

Other hypernyms of applied science include bailiwick, discipline, field, field of study, study, subject, subject field.

applied science (noun)	subject area (noun)
the discipline dealing with the art or science of applying scientific knowledge to practical problems	a branch of knowledge