Who invented the term groupthink?

Solomon Asch is best known for his research on conformity and social influence, particularly through his famous experiments on group pressure and individual judgment. While his work contributed to understanding group dynamics, he did not coin the term "groupthink" nor focus specifically on the pitfalls of group decision-making as Janis did.

Robert K. Merton was a sociologist recognized for his theories on social structure and anomie, as well as for introducing the concept of "role models." Although his contributions to sociology are significant, he did not create the term "groupthink" or specifically address the issues related to collective decision-making that Janis explored.

W. E. B. Du Bois was a prominent sociologist, historian, and civil rights activist, notable for his work on race relations and the concept of double consciousness. His focus was largely on social justice and racial issues, and he did not develop the concept of "groupthink," which emerged from a different context of group psychology.