spiral of silence
The German political scientist Elisabeth Noelle-Neumann coined the term “spiral of silence” in 1974 to refer to a phenomenon that we see often today: people’s willingness to speak freely depends upon their unconscious perceptions of how popular their opinions are. People who believe their opinions are not shared by anyone else are more likely to remain quiet; their silence itself increases the impression that no one else thinks as they do; this increases their feelings of isolation and artificially inflates the confidence of those with the majority opinion.