Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
CHAUNCY
As described in historical dictionaries
Patronymica Britannica (1860)
CHAUNCY. Cauncy occurs in Holinshed's so-called Roll of Battel Abbey, and Chauucy in that of Leland, and the progenitor of the family is said to have come into England with the Conqueror, from a place of that name near Amiens.