It has been identified and logged as a monument, which means someone, at some point, observed enough on the ground to warrant that designation. Beyond that, the record is effectively silent.

An enclosure, in the archaeological sense, is a broad category: a defined area bounded by some combination of earthen banks, ditches, walls, or stone features. The term covers everything from prehistoric settlement sites and early medieval ringforts to later field systems and ecclesiastical enclosures. Without further detail it is impossible to say which tradition this particular example belongs to, or what period it might date from. Kerry has an exceptionally dense concentration of such monuments across its landscape, many of them understudied, and Lassaboy is a relatively small and quiet townland that has not attracted the attention of better-documented sites nearby. That a monument here has been catalogued but not yet fully described is not unusual; it is, rather, a fairly honest reflection of how much of the Irish archaeological record remains to be properly worked through.