Deisal, from Old Irish and Gaelic roots meaning "right hand side" or "southward," names the practice of moving in the same direction the sun appears to travel across the sky, that is, keeping the object being circled on one's right hand as one walks. Early Irish glossaries and legal tracts already treat the movement as ritually significant, prescribing it around a person or place to confer protection, blessing or good fortune, and the practice continued as living folk custom in Gaelic speaking Scotland and Ireland for centuries after Christianisation, applied to houses on first entering them, to boats before a voyage, to livestock, to a new mother and child, and around holy wells and standing stones on pilgrimage.
Early medieval Irish sources place deisal in explicitly religious contexts predating Christian influence, and its persistence as an ordinary, largely unselfconscious element of Gaelic daily custom well into the modern period, documented by nineteenth century folklore collectors such as John Gregorson Campbell in the Scottish Highlands, is among the clearest surviving threads connecting recorded pre-Christian Celtic ritual practice to observable later tradition, even though the specific theological framework that originally justified the gesture is not preserved in detail from the pre-Christian period itself.