The research project is presented that marks out the origin of the meaningful word in babies from the moment of their birth. The reactions of babies were viewed as the elements of their adaptive behavior. The database of the systematic video and audio recordings of behavior of the 5 babies from 0 to 12 months was formed, i.e. in the period that precedes the emergence of the child words – in a so-called “preverbal” period. A special method of analysis of the recordings was developed: 3 types of voice manifestations and 4 types of cognitive-active reactions were distinguished, as well as some other manifestations. In the process of observation the structure of reactions showed up, which includes at least 2 subsystems – vocal and cognitive-active. The diagrams, presented in the article, show the difference in the directions of development of the vocal and semantic subsystems. The author schematically showed the history of emergence of each of them. The early origins of the child speech are connected with the formation of this whole system, while its development starts from the birth of the baby. The author developed the theoretic conception of the origins and development of semantic (subjective) component of baby speech in the first months of life, emergence of rudimentary forms of meaningfulness, and showed the role of operant conditioning in production of first child words.