What is "ballachulish"

The village of Ballachulish ( or , from Scottish Gaelic Baile a' Chaolais ) in Lochaber, Highland, Scotland, is centred on former slate quarries. The name Ballachulish (Ballecheles, 1522 – Straits town,) was more correctly applied to the area now called North Ballachulish, to the north of Loch Leven, but was usurped for the quarry villages at East Laroch and West Laroch, either side of the River Laroch, which were actually within Glencoe and South Ballachulish respectively.