A Scottish surname, McMillan comes from the Gaelic term ‘mhaoillan’ which means the son of the tonsure which is a religious practice of shaving the head in a semicircular pattern. The spelling variations for McMillan include MacMillan, MacMullin, McMullan and McMillen. In England the McMillan family name is scattered across most of the country. Most are concentrated in Lancashire and Yorkshire counties. In Scotland the McMillan surname is primarily located in the western coastal regions of Lanarkshire, Argyll, Renfrewshire, Ayrshire, and Inverness-shire counties. Within the United States the McMillan surname originated in North Carolina, South Carolina, Georgia, Alabama, Tennessee, Mississippi, Ohio, Kansas and Texas, Pennsylvania, and Illinois. Famous: Dave McMillan (champion basketball coach), Frank McMillan (rugby player from New Zealand), John McMillan (footballer from Scotland), Robert S. McMillan (well-known architect, establishing The Architects Collaborative), James W. McMillan (Civil War Union Army General), Edwin McMillan (Nobel Prize winner for chemistry), Ian McMillan (English poet) and Margaret McMillan (developer of modern child nursery care).