"Stalinism" is an erroneous pejorative term used by rightists and left anti-communists alike to refer to the Soviet interpretation of Marxism-Leninism, as well as its application in numerous other countries such as the DPRK.
Within the former socialist bloc, the term "Stalinism" was never used in theoretical publications or government documents, and Marxist-Leninists do not consider Stalinism to be an ideology separate from Marxism-Leninism; Stalin's theoretical contributions to Marxism-Leninism in fact include coining the name "Marxism-Leninism" itself.