The creation of the Slovene Lexical Database is one of the central goals of a major Slovene lexicographic and human language technologies project (Communication in Slovene: http://www.slovenscina.eu). The database should, on the one hand, serve the needs of posterior compilation of monolingual and bilingual dictionaries, and, on the other hand, be robust enough to serve further human language technologies needs. The initial design phase of the database has been aimed at defining the guidelines and principles of the database compilation. In this period, several similar lexical database projects have been scrutinized. The paper presents a review of their features and then focuses on the semantic level of the description of the lexical unit. This level has two subcategories, namely the semantic indicator and the argument structure. The organizing principles of these two categories, especially the latter, are presented along with sample materials.