There are several synonyms for the term "dividing line" that can be used to describe a distinct separation or boundary between two things. Some alternative phrases that can be used include "boundary line", "partition", "demarcation", "separator", "barrier", "boundary", "split", "frontier", "threshold", "partition line" and "dividing border". These terms can be used interchangeably depending on the context, but all convey the idea of a clear separation between two different things. Whether discussing a philosophical divide or a physical border between territories, using any of these synonyms can provide a clear and descriptive way of expressing the concept of a dividing line.