In the beginning of the 19th century, Swedish was the only official language of Finland, and thus the dominating language in administration and higher education. However, during the latter part of the century, efforts were made to develop Finnish into a language which could be used in every part of society. In 1881, the medical society Suomalainen Lääkäriseura Duodecim was founded with the development of a medical terminology in Finnish as one of its main purposes. In 1885, a medical paper, Duodecim, and a medical dictionary were published. The aim of this study is to illuminate the vocabulary of the dictionary. The articles published in Duodecim about the dictionary during the same time are used to get to know the context into which the dictionary was published. In this study, the medical dictionary published in 1885, Duodecim’in Sanaluettelo Suomen lääkäreille, and relevant articles in Duodecim are examined. Relevant articles are read and summarized. From the dictionary, relevant words are selected. The method is qualitative and grounded theory is used. The discussion in Duodecim is mainly, except for some discussion about minor linguistic errors, about what vocabulary is to be used for such a basic phenomenon as respiration. In the dictionary, the most striking trait is the presence of Finnish translations of almost every anatomic term in Latin mentioned. A fear of loan-words is observed. This has also been seen by other authors. Other words are translated directly from Swedish. Some translations are more like explanations than translations.