boundary zone
Edge between regions
A boundary zone is the area where one region, territory, or condition transitions into another.
Unlike a sharp boundary line, a boundary zone acknowledges gradual change or overlap: The boundary zone between forest and grassland supports unique species.
The term appears in ecology, geology, and discussions of contested borders where precise demarcation proves difficult or artificial.
- borderOuter edge or limit
- border crossingTransit between sovereign territories
- edgeBoundary or sharpness
- thresholdPoint of beginning
- marginEdge of a page
frontier · outer limits · liminal · transitional · gray area · in between · buffer · periphery · fringe · interface · membrane · perimeter · fault line · demarcation · crossing · no-man's-land · no man's land · twilight
boundary zoneinterior
Inside area or region
core · center · central region · heartland · nucleus
boundary zonehome base
Central point of operations
comfort zone · native ground · heartland · mainland · solid ground
boundary, zone, bound, bounds, bounded, bounding, boundless, unbounded, boundaries