Coincidence-range finder is a specific type of range finder that determines distance by aligning two images of the same object. However, there are several synonyms for this term that can be used interchangeably. One of the most common synonyms is "stereoscopic range finder," which uses the same principle of aligning two images. Another synonym is "parallax range finder," which measures distance by observing the apparent shift in position of an object when viewed from two different angles. Additionally, "optical range finder" can refer to any type of range finder that uses optical principles to determine distance, including coincidence-range finders. Overall, there are several synonyms that can be used to describe coincidence-range finders, each highlighting a different aspect of their operation.