As described in historical dictionaries

Patronymica Britannica (1860)

FURNEAUX. A Norman family who came either from Fom-neau-sur-Baise, near Falaise, or from Fourneaux-sur-Vire, near St. Lo. They gave the suffix to PelhamFurneux, co. Herts.

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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