A cashel is simply the stone equivalent of a rath, the more common earthen ringfort; where a rath was built up from banks of soil and ditches, a cashel was constructed from drystone walling, often where the local geology made stone the more practical material. Clare's Burren region and its fringes are particularly associated with this kind of construction, where limestone lies close to the surface and timber was historically scarce.

Ringforts in general date mostly from the early medieval period, roughly the fifth to the twelfth centuries, and were the farmsteads of their age, enclosing a family's dwelling, animals, and stores within a defensive perimeter. The name Cahermore itself is an anglicisation of the Irish Cathair Mhór, meaning something like "the great stone fort", which suggests the site was significant enough in local memory to give its name to the surrounding land. Beyond that etymology, the specific history of this particular cashel, its construction date, the families who occupied it, and its later fate, are not currently documented in the accessible record.