The use of the word 'Ban' in the middle of a Gaelic name, such as James Ban Stewart of Miltown of Borenich tells us that he was fair-haired. With so many James Stewarts living in the same area they were difficult to identify as individuals. Obviously the 'Ban' is not part of the name at baptism.
For the same reason you also find the father's name being used as an extra middle name, as in Donald Robert Stewart of Lochaber.
Hope this help,
Isis at
www.borenich.co.uk