The need for separating such terms as «fluctuations» and «successions» for assessing consequences of climatically induced vegetation changes is emphasized. Despite significance, the ambiguity of these terms meaning is noted. The ambiguity is connected with existing different mechanisms of vegetation dynamics, which, in general, are described by two concepts — holistic and individualistic. Attempting to analyze some of terms (e.g., fluctuations, successions, chronosequences, successional step, successional threshold) commonly applied to vegetation dynamics performance, we assume that they are relevant to a holistic concept. In case of vegetation dynamics going as described by an individualistic concept, the phenomenological immanence of the above mentioned terms disappears. They turn into «just terms» and should be only implicated for pragmatic reasons. Besides, we could conclude that chronosequence analysis gives opportunity to reveal a dynamic process as a succession properly. From the other side, in order to determine the direction of dynamic processes, analysis of ecological groups and functional plant types is appropriate.Key words: vegetation dynamics, succession, fluctuation, climate change.