It is broadly circular in plan, roughly sixty metres across, but something about its eastern side breaks the pattern: where the rest of the perimeter curves in the manner typical of early medieval enclosures, that eastern arc runs noticeably straight. Whether this reflects a later alteration, an original design decision, or simply the way the ground lay, is not recorded. A farm track passes along its western edge, running roughly north to south, which gives the enclosure an oddly maintained border on one side while the rest of it recedes into the grass.

Enclosures of this curvilinear type are generally associated with early medieval Ireland, where they served a range of purposes: some were ringforts, the defended farmsteads of farming families, while others enclosed ecclesiastical sites, burial grounds, or areas of unclear ritual significance. The distinction is not always easy to establish from surface features alone, and Moonhall's enclosure remains cautiously classified as just that, an enclosure, rather than assigned to any particular function. What does add a layer of interest to the site is its relationship with the landscape around it: a ringfort lies approximately sixty metres to the south-south-east. The proximity of two such features is not unusual in Irish townlands, where early settlement often left multiple earthworks within a short distance of one another, but it invites the question of whether the two monuments were contemporary, and if so, how they related to each other.