Morphology: cwm+carn
Phonetic: comb-kharrn
This means "valley of the cairn" – referring to Nant Carn, the stream that flows from the top of the hill in to the Ebbw River. This village was originally called Abergwyddon, as shown on Monmouthshire maps up to 1817, but was then renamed Cwmcarn, and appears on maps of Monmouthshire as such by 1820. One tale that describes why this change of name took place is that an English station master could not pronounce Abergwyddon when referring to the railway halt, and so the place name changed to reflect the usage brought about by the necessity of railway travel.