Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.
STEWART
As described in historical dictionaries
An Etymological Dictionary of Family and Christian Names (1857)
Walter, the son of Fleance, and grand-son of Banquo, was created, by Malcom III. Lord High Steward of Scotland, from which office his family afterward took and retained the name of Stewart, and from them descended the royal family of Stuart.
Patronymica Britannica (1860)
STEWART. See Stuart.
Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
Surname type: From given name or forename
Origin: Celtic
Region of origin: British Isles
Country of origin: Scotland
Religion of origin: Christian
Language of origin: Gaelic