This paper analyses architecture semantics at the end of the Middle Ages, starting mainly with Catalonian and Valencian examples. First of all, we examine terms such as mestre d’obres, mestre de cases, and imaginaire, which are often used as synonyms. On the other hand, the study of many other less common ones, such as architect and builder, can help us to clarify a rather complex building reality. The analysis of the documents allows us to strengthen our understanding of the versatility of the medieval master builders, the prestige that some of them acquired, and the relationships that they established with other related professions. [ABSTRACT FROM AUTHOR]