Abstract
This paper is discussing kinship arrangements and more generally families of Western Slavs based on linguistic and corpora data. It is argued here that we can find correlation between lexicon and society, and that studying of lexicon can provide supportive data for society examination. In this paper we used corpora data that provides us with reliable information about lexicon that is truly used by speakers of Western Slavic languages and provided possible explanations for changes occurring in this part of vocabulary. Paper is divided into three main parts, one discussing relations between social reality and kinship terminology, while the second is discussing data from corpora. Third part is devoted to drawing conclusions.