Oge (long 'o') is Irish for 'junior' or 'younger'. It was used when there was someone with the same name or closely related was living at the same time. The senior would have been rendered 'mor'. It does not necessarily mean that this was father son, just a way of telling the difference with the long string of 'macs'. Note: If there was a third one, one could have added 'meodanach' or middle. Hope this helps! Phil