This article focuses on the lexical components active in Gadda's novel “Quer pasticciaccio brutto de via Merulana". The novel is an exceptional example of plurilingualism, therefore Gadda mixes technical terms, literary elements, Latinisms, Greek terms, new forms, and foreign words and phrases (English, French, German, Spanish). Further the collection of Italian dialects (Roman, Milan, Neapolitan, Venetian), the study intends to provide a stylistic analysis of the innovation of Gadda's expression in the lexicon. The results of this linguistic fieldwork sets out to demonstrate also the lexicon and terms of the technical-scientific language of Gadda: for example terms and phrases of physics, engineering, mathematics, medicine, chemistry, biology, mechanics, geology, geography, astronomy, philosophy, theology, linguistics and rhetoric; as Gadda has a competence of the technical terms because of his studies as an electrical engineer at the Polytechnic and later his practical experience. It is an analysis, even elementary, of the linguistic composition of Gadd's prose that can be used to understand the technique of his experimentalism, and how much he knew how to treasure every experience to enrich it and vary it on wider stylistic networks. This linguistic material mixes many ingredients such as: technical and scientific languages, various registers of speech, vernacular, jargons, archaisms, Latinisms, mixed with words of Gadda's creativity, creating what the French called pastiche.