mother country vs country

mother country and country both are nouns.

Word	Noun	Adjective	Verb	Adverb
mother country	Yes	No	No	No
country	Yes	No	No	No

As nouns, country is a hypernym of mother country; that is, country is a word with a broader meaning than mother country:

Other hypernyms of mother country include land, state.

mother country (noun)	country (noun)
the country where you were born	a politically organized body of people under a single government
	the people who live in a nation or country
	the territory occupied by a nation
	an area outside of cities and towns
	a particular geographical region of indefinite boundary (usually serving some special purpose or distinguished by its people or culture or geography)