The site carries a name rooted in Irish, likely derived from "tamhnach" meaning a green field or cultivated patch, combined with a further element suggesting a distinctive local feature, though the precise meaning has softened over centuries of use. That a place can be formally registered as archaeologically significant while its contents remain undisclosed is not unusual in Ireland, where the sheer density of monuments across the landscape means documentation has always outpaced publication.

Achill Island sits off the coast of County Mayo and has been continuously inhabited since at least the Neolithic period. The landscape around Keel, on the island's southern shore, contains a variety of monument types typical of the west of Ireland, from field systems and lazy beds to booley huts associated with transhumance, the seasonal movement of people and livestock between lowland and upland pastures. Whether Tawnaghlaur fits into any of these categories is not something the available record currently confirms. What is certain is that the townland sits within a broader archaeological corridor that runs across Achill, where generations of settlement have left traces in the peat and along the coastal margins.