As described in historical dictionaries

Patronymica Britannica (1860)

FILBERT. Philibert, a French personal name. St. Philibert was abbot of Jumicges in theVII. cent., and several villages in Normandy and Picardy boar his name. From some one of these the filbert-nuts — nuccs de SiDU'to PhUibcHo — are presumed to have been imiorted into England. This nut lias been a particularly hard one for the teeth of etymologists. See Richardson. See also Mr. Blaauw, in Sussex Arch. Coll. vi. 46.

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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