A bullaun is a boulder or large stone into which one or more rounded depressions have been ground, most likely by human hands, though the precise purpose of these cup-like hollows has never been fully settled. Theories range from the practical, grain-grinding or pigment preparation, to the ritual, with many bullaun stones found in association with early Christian sites, holy wells, and places of local veneration. The water that collects in the depressions was often considered to have curative or protective properties, and in some parts of Ireland that belief persisted well into the modern era.

The townland name Treananearla suggests a place with its own quiet depth of local identity, though the recorded details for this particular stone are sparse. What can be said with confidence is that bullaun stones as a class are generally considered to date from early medieval Ireland, roughly the sixth to twelfth centuries, and their distribution across the country is wide, turning up in fields, beside ruined churches, and occasionally in positions that seem entirely removed from any obvious context. That last quality is part of what makes them interesting. They are often overlooked precisely because they do not announce themselves, lacking the vertical drama of a standing stone or the enclosure of a ringfort.