(m) Latin, ‘a Moor.’ Usage of this name in
Scotland probably reflects Irish ancestry. Maurice has long been
used in Ireland as a substitute for Muirgheas, ‘sea choice.’
In the Highlands it also served, e.g., amongst the Macraes, as
a substitute for Muireach—see Murdo. In Scotland the spelling
Morris occurs, but this may derive from the surname (which itself
derives from Maurice).
To Scottish Christian Names