Note: Do not rely on this information. It is very old.
Aber
Aber, a prefix denoting the situation of a place at the mouth of a river or a confluence of waters. It is a word belonging to the Kymric branch of the Keltic stock, the corresponding Gaelic term being "inver." Not a single name beginning with Aber is found on the west coast of Scotland, in Ireland, or the Hebrides; but on the east coast of Scotland and in Wales it is common.