LOUGHOR (THE), a river of South Wales. It rises in the Mynydd-Du mountains in Carmarthenshire; and runs about 15 miles south-south-westward to the head of the estuary called Burry river. It makes a fall, in one place, of 19 feet; and it forms the boundary between Carmarthenshire and Glamorganshire over about 8 miles of the lower part of its course. Its name is properly Llwchwr; and was corrupted first into Lloughor, next into Loughor.

(John Marius Wilson, Imperial Gazetteer of England and Wales (1870-72))