What is the meaning of Czechoslovakia?

When the Austro-Hungarian empire was broken up after WW1, the Czech and Slovak and Ruthenian peoples in the northern part of the empire (but not the Polish people in Galicia, the furthest north) were formed into a new country that had never existed in that form before. It was called Czechoslovakia. The Czechs were the most highly developed and the richest, so they dominated the country. In 1939 the Ruthenian part of the country was transferred to Hungary and in 1945 to Ukraine. Soon after the end of Communism in 1990, the Czechs and Slovaks formed separate countries, the Czech Republic and Slovakia. That is why you won't find Czechoslovakia on the latest maps of Europe.