The Collaborative International Dictionary of English v.0.48:

Unsad \Un*sad"\, a. [AS. uns[ae]d unsated, insatiable. See Un-
   not, and Sad.]
   Unsteady; fickle. [Obs.]
   [1913 Webster]

         O, stormy people, unsad and ever untrue. --Chaucer.
   [1913 Webster]