In Irish, names beginning with "Lios" or "Lis" typically refer to a ringfort, one of the thousands of circular enclosed settlements, usually dating from the early medieval period, that are scattered across the Irish countryside. These were domestic sites, farmsteads surrounded by an earthen bank and ditch, though they accumulated a considerable folklore weight over the centuries, becoming associated in popular tradition with the otherworld and treated with a wariness that, perhaps inadvertently, helped preserve many of them.

Beyond its evocative place name, the documented detail for this particular site is thin at present. What can be said is that Creevard is a rural townland in Mayo, a county whose landscape holds an unusually dense concentration of archaeological monuments, from megalithic tombs on the slopes above Lough Conn to the extraordinary preserved field systems beneath the blanket bog at Céide Fields further to the north. A lios in this part of Connacht would not be out of place; the west of Ireland retained patterns of early medieval settlement that in many areas survived relatively undisturbed into the modern era, partly because of lower levels of intensive arable farming that elsewhere flattened earthworks entirely.