Each concept here is mapped to its prerequisites — the ideas you'd need first to understand it — all the way down to four foundations: Space, Time, Energy, Pattern. Click any prerequisite to drill down, or scroll for the chain graph.
As a pattern of movement through space, entering involves crossing a boundary or threshold, occupying a new position within a spatial region or volume.
External reference — all senses of the word “enter” on Wiktionary. This atlas concept maps to only the slice of meaning relevant to the prerequisite graph.