As described in historical dictionaries

Patronymica Britannica (1860)

AGGAS. Probably the son of Agatha, since such forms as Fil' Agath' and FirAgacie are found in the H.R. See Female Christian Names.

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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