As described in historical dictionaries

Patronymica Britannica (1860)

KIR BY. (In charters, Cherchebeius, and. originally written Kirldjy). Parishes, &c., in cos. Essex, York, A\''arwick, and Norfolk, Places in cos. Lancaster, York, Nottingham, Lincoln, Leicester, and Westmoreland, still retain the form Kirkby, which is also a surname.

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.


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