The material for the study includes one root words of the Buryat language structured with the help of the cluster method. The word-formation nest of Buryat words is not organized as in Russian by the graded method but by the cluster one. The relationship of coderivation or equal derivation is a universal feature of the word-building system of Buryat. The most appropriate term for understanding of Buryat word formation paradigm is the cluster of derivatives.
The article is devoted to the problem of single rooted words modeling by the cluster method. The structuring of derivatives of the same derivational base as a word formation cluster is rested upon the derivational peculiarity of Buryat that represents different ways of word formation and not only affixation. It is characterized by the semantic derivation including composition and its varieties compounding, reduplication, syntactic derivation, etc. As a result derivatives with complex affixes (affixes coalition), derivational synonyms, pair words, reduplicants, compound words, syntactic words, contaminated words, conversives are found in one cluster.
Undoubtedly, one-root lexical class structuring demands different approach: nest modeling requires on an axis rotation, derivational nest peak forming the axis which is traditionally located to the left of all derivatives. In our case the peak is in the center so vertical development results in consecutive derivation (in the given paper a consecutive chain of derivatives is named as “branch”), horizontal development results in one level clustering (in the paper derivatives with the same derivation base are named as fan of derivatives).
In the paper we conclude that a derivational cluster reflecting systematic organization of Buryat one-root words reveals an important feature of word formation potential of Buryat words - derivational relations. These relations are mostly coderivative. In this connection Buryat derivational nest appears as a paradigm represented by extensive clusters and short branches.