Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.
KELSO
As described in historical dictionaries
An Etymological Dictionary of Family and Christian Names (1857)
(origin: Local) Derived from the town of Kelso, in Roxburghshire, Scotland. Kelso was originally written Calchow, a corruption of Chalkheugh, the chalk-hill.
Patronymica Britannica (1860)
KELSO. A town and parish in Roxburghshire. The family were in Ayrshire at an early period. Hugh de Kelso is mentioned in Ragman Roll, 1296. B.L.G.
Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
Surname type: Location or geographical feature
Origin: Celtic
Region of origin: British Isles
Country of origin: Scotland
Religion of origin: Christian
Language of origin: Gaelic