EN
It seems that a lie is a well-understood term. However, on the scientific ground, there is no precise and commonly accepted definition of a lie. There are various proposals how to understand it in psychology, in the theory of communication, and linguistics. In the paper, there is proposed such a definition which could be useful in the fields just mentioned, as well as in the educational sciences. Especially, from the practical point of view an accurate meaning of lying should be important for pedagogues, educators, and teachers. Moreover, a proposed definition of a lie can become the base to define, as precisely as possible, another apparently vague term: psycho-manipulation.