Lang, Laing
Lang, Laing—These two names in Kintyre and the Province of Galloway are the anglicised forms of a sept of the McDonalds in Kintyre called O'Loynachan, changing the name in the 18th century.
Alphabetical Index of Anglicised Surnames in Ireland
See also Woulfe’s Irish Names and Surnames
… and O'Hart's Irish Pedigrees