country vs kingdom

country and kingdom both are nouns.

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

As nouns, kingdom is a hyponym of country; that is, kingdom is a word with a more specific, narrower meaning than country:

country (noun)	kingdom (noun)
a politically organized body of people under a single government	a basic group of natural objects
the people who live in a nation or country	a monarchy with a king or queen as head of state
the territory occupied by a nation	the highest taxonomic group into which organisms are grouped; one of five biological categories: Monera or Protoctista or Plantae or Fungi or Animalia
an area outside of cities and towns	the domain ruled by a king or queen
a particular geographical region of indefinite boundary (usually serving some special purpose or distinguished by its people or culture or geography)	a country with a king as head of state
	a domain in which something is dominant