This work is an attempt to study the phenomenon of doubling monosyllabic and two-syllable words that may represent different parts of speech in the English, French and Ukrainian languages, analyze peculiarities of reduplication of nouns and other parts of speech. Examples of different types of reduplication and their application are presented. The article also considers variants of doubling words from semantic and stylistic points of view. To conduct the research, a mixed research methodology has been used: continuous sampling method, comparative method, method of observation.Doubling raises two considerations related to form and meaning. In terms of form, the term "reduplicant" is broadly used to refer to the part of a word that is repeated, while "stem" is used to refer to the part of a word that provides the source material for reduplication. The article examines key issues concerning the reduplicative form, the theory of base-duplicate identity, the form of duplicates, and the factors that should be considered when determining the base of reduplication. A defining feature of reduplication is that it involves copying part of a word. This linguistic phenomenon gives rise to a wide variety of mechanism that explain how repetition occurs.It is stated reduplication is characteristic of many speech styles, although it predominates in the language of children. The biggest number of reduplicants were found in the French language, with English comes the second. In Ukrainian, this linguistic phenomenon is not so frequent, although it is typical of poetic or expressive speech. Reduplication as a language technique and a way of forming new language units is a little studied subject. The mechanism of such word formation, the meaning and function of reduplicates require more careful consideration, as a widespread phenomenon. The study of reduplication aroused our interest from the point of view of understanding a number of properties associated with the process of word formation.