Kilmaganny derives from the Irish Cill Mocheannaigh, meaning the church of Mocheannach, a reference to an early Christian saint associated with this locality. That a settlement this small should preserve such a direct line back to the early medieval period, encoded in the very syllables people use to name the place, is the kind of detail that rewards attention.

The presence of a graveyard on or near the site of an early church foundation is a pattern repeated across Ireland. Communities tended to bury their dead on consecrated ground that had been in continuous use for centuries, sometimes millennia, layering Christian practice over older sacred topography. In many such Kilkenny sites, the remnants of a medieval parish church survive within or adjacent to the burial ground, reduced over time to a roofless shell or a scatter of dressed stone. The saint's name attached to Kilmaganny places its origins within the broader flowering of monastic and ecclesiastical settlement that shaped the Irish landscape between roughly the sixth and twelfth centuries.