sourde

from The Collaborative International Dictionary of English v.0.48

Sourde \Sourde\, v. i. [F. sourdre. See {Source}.]
   To have origin or source; to rise; to spring. [Obs.]
   [1913 Webster]

         Now might men ask whereof that pride sourdeth.
                                                  --Chaucer.
   [1913 Webster]