The text discusses the wordsmi(e)zyniec, mizynek ‘little finger’, ‘youngest child, calf, piglet, chicken’. A few decades ago, K. Nitsch dedicated a separate study to this subject, published in the Język Polski journal. Our text, contingent on the methodologies of linguistic geography, presents the history and geography of these words in Polish within the broader Slavic context. It follows from the findings that the individual forms from the *měz- stem are to be differently viewed. Some forms may certainly be seen as relics of the early Slavic unity and cannot be treated as lexical borrowings. Besides, some forms, especially the *mězinъkъ deriva-tive which has no equivalent of the mie- form in the Polish language, can be seen as a Ukrainian loan word.