Here's what I found out on visiting several French genealogical web sites. Dendurent, as we have long surmised, is probably an English spelling corruption. The name variants according to the genealogical sites include "Dandurand," "Danduran," "Andurand," "Anduran," "Andurant," "Enduran," and "Durand."
Following is my translation of one source.
The name is especially known in Aveyron and Cantal [departments of France]. One meets it in Gascogne [a region] in the Danduran form. See Anduran.
Andurand: It is in Aveyron that the name is most widespread. Alternatives: Anduran, Andurant, Enduran. One can certainly see in the surname the suggestion of an enduring, patient man, but another solution is possible: the name Durand, preceded by the Occitan particle "en" (in general marking a higher degree in the social hierarchy).
Last possibility: the final form of a medieval baptismal name. The names Danduran, Dandurand designate for their part the son of Anduran(d), or else for one called "dam Durand" ("dam," from Latin "dominus", similar to "don" [in Spanish]).
Aveyron and Cantal are departments (~ states) in south central France. Gascogne is the regional name for the area from Bordeaux down to the Spanish border.
Of the three possibilities, the last two suggest some sort of social rank. Due to the fact that our ancestors, not only the "Dendurents" but also many of the other names in our family tree, wandered through countries like Holland and Germany before they arrived in America, I'm convinced they were Huguenots, driven out of France in the late 17th century by King Louis XIV. They would have had to have the means and so could not have been peasants.
The names in our family tree include the following: Truax/Truex/du Truy, Larue/le Roux/de la Rue, Gillet, D'Uzille/Uzille, Cosier, Post/Pos, Dufour/du Four, Antoine, Bonen, du Chesne/Duchêne. Note the variants of the names, a consequence of the fact that uniform spelling has only been in place for a couple of hundred years.