“Tankie” was a pejorative for Marxists that support socialism in real life then as well as now. It originated in the Communist Party of Great Britain. The term was coined because of the British tendency towards silly-sounding insults, and because the Soviet Union sent in the Red Army to stop the western-backed fascist insurrection. This caused a split in the party (as it always does in western orgs).

Do you know if it’s rhyming slang, and if so, what the phrase was?