As described in historical dictionaries

An Etymological Dictionary of Family and Christian Names (1857)

(origin: Local) A corruption of Derby, a shire of England, so called from doire, a forest, a woody, hilly country abounding in deer; or it may be Deerby, the town of deer.

Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.


Patronymica Britannica (1860)

DARBY. A corruption of Derby. So Darbishire from Derbyshire.

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: English

Region of origin: British Isles

Country of origin: England

Religion of origin: Christian

Language of origin: English

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