The proposed research is dedicated to the study of the AMERICAN DREAM linguocultural concept in its diachronic development (16th - mid. 20th century) in the American language world picture. The thesis highlights the linguocultural approach to the study of mental units. The terms "concept" and "notion" are interpreted in the work. Within the framework of the research a linguocultural concept has been determined as a cultural multi-functional phenomenon which accumulates the knowledge about a certain fragment of reality in the collective consciousness of the linguocultural unity. It serves as a mirror for cultural values, is objectivated by means of language elements and is linguoculturally marked. The approach based on the conception of the semantic structure of the linguocultural concept which includes notional, imaginary, valuative, symbolic, national-cultural and ideal components has been worked out and applied. The semantic evolution of the AMERICAN DREAM concept has been influenced by the cultural, religious, social and historical circumstances. First pilgrims came to the American continent (early 16th century) with the dream to start a new life, to live free and become rich. The notion of American dream was evolving. In the 16 17th centuries the basic notional features of the AMERICAN DREAM concept were Equality and Unity; in the 18th century - Equality, Unity, God providence, Industry, Honesty, Freedom, Pursuit of Happiness; in the 19th century - Freedom, Success, Work, Ability, Opportunity, Happiness, Equality, Wealth tоgether with Inaccessibility; in the early - mid. 20th century - Opportunity, Money, Choice, House, Car, Рlot of land, Farm аs well as Inequality, Inaccessibility, Unfairness. These conceptual features are accompanied by various connotations which lead to the evolution of the AMERICAN DREAM concept. In the mid. 20th century economic changes (falling production, financial crisis, unemployment) evoke the changes in the American value system. The ideas about the American dream decline, collapse, fall are becoming widespread. Therefore, the mid. 20th century is the beginning of a new stage of the concept development. In the process of research it is proved that the AMERICAN DREAM linguocultural concept gradually develops its semantics and is explicitly reflected by the place of an individual in the world and the estimation of the surrounding reality.
