The aim of this article is to try to differentiate the notions of fashionable words and key words of the modern times. The comparative analysis of these linguistic phenomena is presented in this work. The author comes to the conclusion that fashionable words characterize the aesthetic tastes of society, have a bright outer shell, in the center of attention of native speakers are short time. The key words of the modern times depict values, cultural priorities or outlook of society of the given time and are able to influence the formation of the picture of the world for a personality.