A Big Man refers to a highly influential individual in a tribe, especially in Melanesia and Polynesia. Such person may not have formal tribal or other authority (through for instance material possessions, or inheritance of rights), but can maintain recognition through skilled persuasion and wisdom.

Poor Man, Rich Man, Big-man, Chief: Political Types in Melanesia and Polynesia*
The Rule of Law versus the Big Man
‘No Raila, No Peace!’ Big Man Politics and Election Violence at the Kibera Grassroots
Leadership and Individuality in South Asia: The Case of the South Indian Big-man
Doctor, Lawyer, Wise Man, Priest: Big-Men and Knowledge in Melanesia
Big Man, Big Heart? A Mesoamerican View of the Emergence of Complex Society
LE ? BIG MAN ? EN AFRIQUE: ESQUISSE D'ANALYSE DU POLITICIEN ENTREPRENEUR
BIG MAN IN THE MIDDLE
Capitalizing the big man: Yao Ming, Asian America, and the China Global
Africa's new big man rule? Pentecostalism and patronage in Ghana