Fanciful suggestions for the origin of the name have included a truncation of "God's Plot", as the land belonged to the Bishop of Llandaff in medieval times, and a derivation of "plat", meaning a grassy area of land. The name of the original farm would seem to be Middle English "splott", from Old English (speck, blot, patch of land) and the word is to be found in other English place names in the Vale of Glamorgan, Gower, and Pembrokeshire, as well as in Somerset and Devon, in the West Country of England, from where it was presumably introduced by English settlers. It has frequently been noted on lists of unusual place names.