- A patronymic Welsh and English surname; derived from Watkin a pet name for the given name Walter. Originally 'ap Gwatkyn' or 'ap Gwatkin', meaning 'son of Watkin'.
- "Captain Gwatkin, of the brig Scout, had a narrow escape on the 28th ult. In attempting to step from the wharf on board his vessel, he missed his footing and fell into the river." The Courier. Hobart, Tasmania. 7 June 1845. 
- Bardsley, Charles Wareing Endell, A dictionary of English and Welsh surnames: with special American instances, Genealogical Publishing Com, 1996. p. 344-345