What was a blacklist in the cold war?

Answer 1

It was a list of people considered to be enemies of the state (Federal Government) or spies. These people were either interned or arrested and tried. It did not matter what their racial or national background was: if they suspected or had proof of someone being an enemy of the state they were dealt with.

Answer 2

the blacklist during the cold war was basically saying that television and radio workers like actors or film writers were communist, former communist or communist sympathizers.