Jean Lagadeuc References Jean Lagadeuc French lexicographer Ask Anything Homework Help Written by The Information Architects of Encyclopaedia Britannica The Information Architects maintain a master list of the topics included in the corpus of EncyclopĂŠdia Britannica, and create and manage the relationships between them. The Information Architects of Encyclopaedia Britannica Britannica AI Ask Anything Learn about this topic in these articles: Celtic literature/ The three major periods of Breton literatureâŠthere appeared the Catholicon of Jean Lagadeuc, a BretonâLatinâFrench dictionary printed in 1499, and Quiquer de Roscoffâs FrenchâBreton dictionary and conversations (printed 1616). Read MoreâŠthere appeared the Catholicon of Jean Lagadeuc, a BretonâLatinâFrench dictionary printed in 1499, and Quiquer de Roscoffâs FrenchâBreton dictionary and conversations (printed 1616). Read More