The term "nation-state" is frequently misused while the words "nation" and "state" are commonly confused in geographic context. So here is a handy guide to understanding the terms "nation," "state," and "nation-state."
A nation is a group of people who share some, if not all, common traits like religion, ethnicity, language, culture, and history. Nations start out in one geographical area but can move, expand, or shrink in zone. Most nations have a strong ethnic component (Hungarian, Japanese) while a few exceptions are based on things like religion and history (Arab) or ideals like liberal freedom (American).
A state is an independent country. "State of Israel" means the country of Israel. Many Americans are confused by "state means country" because of the official name of their country, the United States of America. The reason for the official name is that the founding fathers envisioned the United States as a league of independent states united for commerce and defense. It was not until the end of the American Civil War that the dominance federal union was proven above the state.
A nation-state is a country established for the dominant nation within its border. For a true nation-state the primary nation needs to be the overwhelming majority group in the country.
Stateless Nations: Roma and Samaritians
Multinational State: Spain, Switzerland, Bolivia
Nation with more than one state: The German nation with Germany, Austria, Luxembourg, Liechtenstein, and Switzerland (65% ethnic German but with never interested in union with other Germans)
Single-nation politically dominant over other nations in one state: Russians in Russia compose eighty percent of the population (formerly 50% of the Soviet Union) yet have always been above other ethnic groups for centuries. Han Chinese have also dominated multi-national China.
True Nation-State: Over ninety-percent Hungarian with laws that enshrine Hungarian culture.