A socialist republic is a republican country that claims to operate under some form of a socialist economic system.
Some nations go so far as to actually use the word "socialist republic" in their official name, for example the "Democratic Socialist Republic of Sri Lanka" or the "Socialist Republic of Vietnam".
Other nations that have claimed to be socialist republics include North Korea, Cuba, and the People's Republic of China. The Soviet Union was made up of numerous socialist republics, and the country's full name was the "Union of Soviet Socialist Republics."
Socialist republics operate under their own interpretation of Marxist doctrine, and usually claim to be executing Marx's envisioned dictatorship of the proletariat. The main organ of a socialist republic is the politburo. A institutionalized Communist Party is often common, as well.
See also: Soviet Republic