As described in historical dictionaries

Patronymica Britannica (1860)

BILLY. N'otfrom'\Yilliam,butfrom aplace in thearroudissementof Caen, inNormandj'. Also a comrade, compaiuon. Jamiesou.

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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