The article focuses on the study of the mechanisms that create nomination of wordcombinations and nomination of composites on the material of compound structured formations in flora namings. This study is relevant, because in theoretical works external (accent-graphical, distributive - va-lent, structural-morphological) properties of nominative flora wordcombinations and nominative flora composites have been considered. External onomasiological presentation of lora surroundings have been thoroughly studied. But there is internal presentation of nomination which is explained by the aspects of logic-semantic codimension and semantic volume of a defining component and a defined component in compound structured formation. Components' content of such a formation is represented in terms of logical binary oppositions of hyponyms and hyperonyms. Direct volume nomination of wordcombinations is archieved by codimension of nominative properties of their components without deinition information. On the contrary, composite nomination of plants' objects of the world is both non-direct and indirect in endocentric composites. Nominative codimension of components in en-docentric composites is achieved not only by the volume of their codimension, but also by the relevant information of the initial elements in the deinition. The irst modiied components, as a rule, are explicited by the phenomena of case semantics (non-direct nomination) and by metaphors (indirect nomination). Composite nomination in exocentric composites of lora namings is wholly indirect from nominative viewpoint. Cod-imension of implicitly expressed modiied component and basic component is achieved exclusively by the extensive relevant information of vocabulary deinition.