"Zone boundaries" refers to the imaginary lines or limits that separate different areas or zones. They define the edges or borders of a specific area, indicating where one zone ends and another begins. Full definition
Companies in these categories are eligible for benefits regardless of whether they are located within previously designated zone boundaries. (bcnys.org)
Dogs with different zone boundaries, and rules for those boundaries, than the people it lives with are going to find themselves in conflict. (samthedogtrainer.com)
According to SETI Institute scientist Isabel Angelo, the study of planets similar to the Venus analog Kepler - 1649b is «becoming increasingly important in order to understand the habitable zone boundaries of M dwarfs. (astronomynow.com)