In Irish, the name derives from "Ceathrú na Creige", meaning the quarter of the rock, a straightforward description that points to a landscape shaped by the underlying geology of the west of Ireland, where limestone and harder outcrops define the character of the land and, by extension, the names given to the places settled upon it. Townland names of this type are among the oldest layers of human geography in Ireland, preserving in compressed form the observations of communities who organised land by the quarter, a unit of agricultural division used widely across Connacht.