Since its beginnings in the first decades of 19th century, the basic musical terminology has always been one of the weakest points of Croatian institutional music education system. Most of the terminological difficulties beginning with Franjo Kuhač’s attempt to translate Lobe’s Katechismus der Musik, described in the foreword of his work, are still present in contemporary musicological discourse: polysemy, homonymy, foreign words and expressions, lexical voids etc.509 The mentioned issues are most obvious from the teachers’ perspective, especially in the state-funded parallel music education system. Therefore, the standardization of contemporary musical terms imposes itself as an important scientific and general task for all its participants. The importance of the task arises from the privileged position of musical metalanguage, especially within the institutional music education discourse. The dissertation is an interdisciplinary attempt to set up a normative language standard within Music Theory regarded as a subdiscipline of Musicology, limited to the context of the so-called “Music Theory Subjects” (“teorijski glazbeni predmeti”510) in the Croatian institutional music education system (parallel elementary and secondary music schools, music academies). The thesis supervisors are Nikša Gligo, musicologist (Music Academy, University of Zagreb) and Maslina Ljubičić, linguist (Faculty of Humanities and Social Sciences, University of Zagreb & Faculty of Humanities and Social Sciences, University of Split). The basic premise was that contemporary Croatian musical terminology is severely heterogeneous, crowded with inappropriate terms like synonyms, loanwords, homonyms, heteronyms, archaisms, semantically or morphologically doubtful constructions and many other terminological issues and thus requires a thorough scientific processing from both linguistic and musicological aspects respectively. The above mentioned problems are tightly connected with the inconsistency of the conceptual systems among Croatian music theorists, especially the authors of educational literature and teaching staff in general. The research was based upon the achievements of a former state-funded scientific project led by Nikša Gligo, the Croatian Musical Terminology (Hrvatska glazbena terminologija, conducted from 1991 to 1993). The applied normative criteria meet the standards determined by the language experts of the Institute for Croatian Language and Linguistics in Zagreb, intended for contributors of their terminological database Struna511 (e.g. Hudeček & Mihaljević 2009). The main point of departure was a corpus analysis of the authorized educational literature (authorised subject-specific textbooks and other educational literature approved by the Croatian Ministry of Science, Education and Sports; authorised curricula for elementary and secondary music schools, music academies and other music subjects taught at universities and other literature used in teaching music theory). In order to show the discrepancies between the usage, norm and variation in written and spoken musicological discourse, a short survey was conducted among teaching professionals and students of music theory and music education. All terms showing any essential variation in usage were considered worth further scientific elaboration and categorized by the type of represented terminological issue. A contrastive analysis of disputed terms was conducted within the context of special field terminologies of foreign languages which influenced the formation of Croatian music theory terms. Earlier Croatian variants of these terms were taken into account when necessary. The conceptual history of the terms was discussed in special cases of polysemy caused by their diachronic development and modifications. The need for a historically-informed deviation from the general terminological standards was disputed in appropriate cases. All terms were carefully observed in their hierarchical conceptual contexts. The research reflected upon the inconsistencies within conceptual systems of different authors and brought some solutions corresponding with the current state of musicological thought. The hypotheses that synonymy and polysemy represent the main source of problems in today’s discourse on music theory were confirmed. The research also offers a set of standardized Croatian music theory terms within an organized conceptual framework harmonized with the general lexical norm, as seen from the contemporary musicological standpoint. Such a normative database should however remain an open form whose permeability and flexibility would enable upgrading and development in order to correspond to requirements of future musicological discourses. The public is offered a referential terminological study to support field experts, students, translators and other users in their approach to music theory in Croatian language.