Calum \c(a)-lum\ as a boy's name is pronounced KAL-um. It is of Scottish and Gaelic origin. Variant of Columba (Latin) "dove". This was popular among early Christians because the dove was a symbol of gentleness, purity, peace, and the Holy Spirit. Saint Columba was an influential sixth-century Irish missionary who founded a monastery on the Scottish island of Iona. His contemporary, Saint Columban, also Irish, was a missionary in France, Switzerland, and Italy. Calum and its variant Callum may be considered variants of Malcolm in Scotland.