As described in historical dictionaries

Patronymica Britannica (1860)

|° DU. The initial syllable of many surnames of Fr. origin naturalized amongst us. It is of course the preposition rZcconjoined with the article le, and answers a purpose similar to that of atte in 0. Eng. surnames; for instance Dubois is 'of the wood,' (our Wood or Attwood) ; Dubosc, 'of the thicket,' (our Shaw); Dubourg, ' of the burg,' (our Burrowes) ; Duchesne and Ducane, ' of the oak,' (our Noakes); Dufour ' of the oven ;' Dufort 'of the fort;' Dupree, Duprej', {pre) 'of the meadow,' (our Mead); Dupuy ' of the well,' (our Wells); Duvall, Duval, 'of the valley,' (our Dale) ; and many others.

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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