military science vs subject

military science and subject both are nouns.

Word	Noun	Adjective	Verb	Adverb
military science	Yes	No	No	No
subject	Yes	Yes	Yes	No

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

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

military science (noun)	subject (noun)
the discipline dealing with the principles of warfare	something (a person or object or scene) selected by an artist or photographer for graphic representation
	a branch of knowledge
	some situation or event that is thought about
	the subject matter of a conversation or discussion
	(grammar) one of the two main constituents of a sentence; the grammatical constituent about which something is predicated
	(logic) the first term of a proposition
	a person who owes allegiance to that nation
	a person who is subjected to experimental or other observational procedures; someone who is an object of investigation

military science (adjective)	subject (adjective)
	likely to be affected by something
	being under the power or sovereignty of another or others
	possibly accepting or permitting

military science (verb)	subject (verb)
	make accountable for
	cause to experience or suffer or make liable or vulnerable to
	make subservient; force to submit or subdue