x1 is a rodent [can be a member of eutherian mammal Rodentia; semantic broadening might subjectively generalize the concept somewhat] of subtaxon/type/genus/species/breed/variety x2
gismu version of: ratcnrodentia, rontnrodentia. Meant for any rodent in general (more general than ratcu, smacu). Semantic broadening may allow for any "small, scurrying mammal" to be so named. For the subjective generalization of concept to any "small scurrying mammal" made explicit, unambiguous, and clear: rontysmimabru.