The first one is in Gaelic Am Bealach ‘the pass (through mountains)’. The Inverness-shire name, however, represents Baile an Loch ‘the farm of the loch’; in the nineteenth century it was spelt Ballinloch. Recently, it has been suggested this latter name also derives from bealach, denoting the pass through which the soldiers went to the Battle of Culloden, but this is of course fanciful; the name predates that event.
Given the difference in the Gaelic forms of the name, it is perhaps not surprising that the names are pronounced in English, with different stress patterns. The Dunbartonshire name is stressed on the first syllable BAL-loch, just as it is in Gaelic. The Inverness-shire name stresses the second syllable, Bal-LOCH, as expected.
This is an excellent example of the adage: ‘Place-names are not always what they seem’.
For more information visit Ainmean-Àite na h-Alba