MacDonald, Macdonald, and McDonald are Anglicised forms of the Scottish Gaelic and Irish Gaelic name MacDhòmhnaill, which in modern Gaelic is approximated as McConnell. It is a patronym where Mac means "son" and Dhòmhnaill means "of Dòmhnall". The personal name Dòmhnall is composed of the elements domno "world" and val "might", "rule". According to Alex Woolf, the Gaelic personal name is probably a borrowing from the BritishDyfnwal.
