A bullaun is essentially a large stone, often glacial or naturally occurring, into which one or more rounded depressions have been deliberately carved. The purpose of these hollows has been debated for generations; suggestions range from the practical, grain-grinding or the preparation of pigments, to the ceremonial, with many bullauns later becoming associated with holy wells, cursing rituals, or patterns, the local gatherings held on saints' feast days. The water that collects in the hollows was frequently considered to have healing or protective properties, and the stones themselves were often venerated long after the formal Christianisation of the landscape around them.

Letter More, a townland on the western seaboard of Connemara, sits within a landscape that carries considerable early medieval and pre-Christian material, though the specific history of this particular stone remains, for now, thinly documented in the public record. What can be said is that bullauns of this kind tend to cluster near early ecclesiastical sites, boundary areas, or places of long-term settlement, and their presence in a townland is rarely accidental. The name Letter More itself derives from the Irish Leitir Mór, meaning the large hillside or slope, a toponym that suggests a landscape shaped as much by its terrain as by the communities who have worked it.