Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.
WILLOUGHBY
As described in historical dictionaries
An Etymological Dictionary of Family and Christian Names (1857)
(origin: Local) From the lordship of Willoughby, in Lincolnshire, England, given to a Norman knight by William the Conqueror.--The town or habitation by the willows.
Origin: English
Region of origin: British Isles
Country of origin: England
Religion of origin: Christian
Language of origin: English