Within the framework of pronunciation, morphology, and syntax, linguistic doubts and uncertainties belong to the everyday business and everyday life of linguists and public speakers. Cases of lexical semantic doubts, however, have been brushed aside by post-Saussurian and all the more by post-Bloomfieldian linguists so far. This paper deals with such lexical semantic doubts and uncertainties which not only rise from language use within "parole" but are caused by a conflict of opposite or even contradictory language norms of different "langue"-varieties (e.g. the adjective positive as a medical term and in everyday colloquial language). Proceeding from an intensive discussion of the relationship between language use, language norms, and language system with special reference to Saussure, Hjelmslev, and Coseriu, the paper presents a theoretical approach to linguistically founded criticism of semantic norms by way of embedding lexical semantics into a framework of "Existenzweisen" (focusing on language use, norms, and system), "Existenzformen" (in particular norms of special discourses and varieties), and "language history and social stratification" (in particular age-based vocabularies and semantics). Finally, the paper turns this theoretic approach into practice by way of describing, explaining, and solving semantic doubts of the German word Zigeuner (gipsy). This example taken from the discourse on "political correctness" is investigated in the broader context of the word's historical, semantic, and pragmatic dimensions in different German discourses and varieties. The systematic relations between the various usages are presented in the form of a pragmatic and semantic network displaying the interconnections and borders between the meanings and gives recommendations to the word's use.