Watson, Watt
Watson, Watt—These two names are the anglicised forms of M'Quatt, McVitty, M'Quitty and M'Whatty in Scotland and in Ulster (Mac Bháididh).
Other forms are M'What and M'Whattie.
Alphabetical Index of Anglicised Surnames in Ireland
See also Woulfe’s Irish Names and Surnames
… and O'Hart's Irish Pedigrees