The lexicon is the fastest changing component of a language. The dynamics of lexical change correspond to changes in reality and to social and political, both non-linguistic and linguistic, influences.
Even the every-day language user can observe the emergence of new lexical forms in relation to newly emerging facts and developments. However, the changes and shifts in the semantics of the lexical items are more subtle.
The article focuses mainly on changes in the denotative meaning, and related connotative changes are also mentioned. As an example of a lexical item whose understanding and usage have altered radically over the course of several decades the word "rozšafný" has been chosen.
The word appears in all core Czech dictionaries; therefore, it cannot be considered to be exclusively on the periphery of the language. Despite this, the meaning of the word given by the dictionaries is very different from the understanding of the word prevalent among language users.
The article employs the Czech National Corpus data and compares them with the results of a research survey among university students.