Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.
GILCHRIST
As described in historical dictionaries
An Etymological Dictionary of Family and Christian Names (1857)
(origin: Gaelic.) From gille, a servant, and Chriosed, Christ--the servant of Christ.
Patronymica Britannica (1860)
GILCHRIST. (Referred to, but accidentally omitted in the body of the work). See under Gill in this Supplement.
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 name of parent
Origin: Celtic
Region of origin: British Isles
Country of origin: Ireland
Religion of origin: Christian
Language of origin: Gaelic