The article presents the results of the onomasiological analysis of the names of medicinal plants or phytonyms. The research is based on the ternary onomasiological model, which includes a basis, feature, and predicate. Emphasis is placed on the basis zone and two bases: a person and an artefact. The research shows that the basis zone includes four varieties of the basis: a suffix, an exocentric compound word, a so-called split basis, and a meaningful word. Lexical bases designate not only the plant itself and its part, but also other things, which are examples of indirect designation.