dividing line 
noun
1The boundary between two areas: the dividing line between eastern and western zones...
- The couple's first piece of furniture, a primitive farm table, is the dividing line between the kitchen and sitting area.
- It was so undesirable that residents of the tony Back Bay area built a fence along the dividing line between the two neighborhoods.
- For millenniums, the frontier between these two countries has been the dividing line between contending empires - and so it is again.
1.1A distinction or set of distinctions marking the difference between two things that are closely related: the smudged dividing line between drama and reality...
- Views will differ as to where the dividing line should be drawn.
- The imposition of order necessarily creates boundaries and dividing lines - the very places where the most interesting discussions occur.
- The old line, the heretofore uncompromising line, the dividing line between matter and spirit has suddenly blurred.
- patterned ground
- patterner
- patternisation
- patternism
- patternist
- patternization
- patternize
- patternless
- pattern-like
- pattern-maker
- pattern matching
- pattern-molder
- pattern-moulder
- pattern paper
- pattern practice
- pattern reader
- pattern recognition
- pattern room
- pattern-setter
- pattern-setting
- pattern shop
- pattern variable
- pattern-welded
- pattern welding
- pattern wheel