"KILMALCOLM, town and parish in lower ward of Renfrewshire. ..... The parish measures 7½ miles by 6½ comprises 19,665 acres. ..... Pop. 2708. The south-eastern section is a shelving valley, traversed by upper part of Gryfe river; the northern section is a slope from left flank of that valley downward to the Clyde; the south-western section is mostly moss; and the western section is mostly waste or pastoral hill. Chief residences are Duchall, Carruth, Finlayston, Broadfield, and villas on the Clyde."
From The Gazetteer of Scotland, by Rev. John Wilson, 1882.
Various gazetteers differ as to the origin of this placename. For a period in the 18th century, Kilmacolm was generally spelled 'Kilmalcolm', based on a presumption that the settlement's name was derived from Malcolm III, one of the former kings of Scotland. In 1905 the accepted spelling became 'Kilmacolm', the general consensus now is that Kilmacolm takes its name from the Gaelic language meaning a cell or church of Columba, derived from the dedication of its ancient church to St. Columba of Iona.
You can see maps centred on OS grid reference NS360696 (Lat/Lon: 55.891566, -4.624105), Kilmalcolm which are provided by: