This research report presents a comprehensive reassessment of the etymological and socio-historical roots of the term "Freemason." Challenging the traditional Anglo-centric interpretation—which derives the prefix "Free-" from the working material ("freestone") or from municipal guild freedoms ("Freedom of the City")—this study develops and tests the "Mascon Hypothesis." This theory situates the genesis of the term within a specific spatio-temporal framework: Burgundy between 1090 and 1150, during the construction of the third abbey church at Cluny (Maior Ecclesia). The study analyzes the social status of the specialized artisans (artifices) hired by the Abbey of Cluny, who operated from a logistical base in the city of Mâcon (historically Mascon). Furthermore, the work examines the transfer of this know-how and terminology to England through the founding of Lewes Priory by the de Warenne family, representing a historically documented channel for the import of Burgundian masters. The core of the paper is a linguistic analysis of the phonetic convergence between the Old French designation of origin (Li Franc de Mascon) and the professional designation (Maçon/Masson) within the Anglo-Norman environment. The report concludes that "Freemason" is likely a corrupted geographical and status-based designation for the elite Cluniac builders who enjoyed the status of free men (liberi/francs) and whose origin from Mâcon became synonymous with the highest construction quality.