This name, which means the Son of Walter, comes through the diminutive Wat or Watt. The full form, Walterson, which has almost died out, was at one time common. A John Watson held lands in Edinburgh in 1392; John Watsoun was a juror at Lanark in 1432. By the 16th century, the name was widespread throughout the Lowlands. A Highland form was found in Moray and the Black Isle, where it appears as MacWatt; Donald and Gilbert Makwat, in 1455, acted as Kingas Courieras. The Caithness MacWatters is taken to be a form of the same name. Watt and Wattie have similar origin.
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