 In a sense, then, "plates" are a heuristic—rather like fitting a straight line through a set of points without a clear functional relationship.Analogously, the term "mesoplate" was introduced.Since the hotspots of the Hawaiian set appear to form a frame of reference (like points on a lithospheric plate, they don't appear to be moving at a very great rate relative to one another), the hotspots and that part of the upper mantle in which they are embedded is termed the "Hawaiian mesoplate".