EN
The article describes the structure of 940 medical terms (names of diseases) from the “Dictionary of Polish Medical Terminology” (Słownik terminologii lekarskiej polskiej) of 1881, that have been recognised as the most accurate, i.e. primary synonyms. From their analysis in the context of synonymic chains in which they occur, it was concluded that the structure of a term recognised as ideal is of no great significance (in the case of 80% of terms) for the establishment of the term as the primary synonym. This is one of the reasons for which primary synonyms often have a structure identical to other terms in its synonymic chain.