The Collaborative International Dictionary of English v.0.48:

Appay \Ap*pay"\, v. t. [OF. appayer, apaier, LL. appacare,
   appagare, fr. L. ad + pacare to pacify, pax, pacis, peace.
   See Pay, Appease.]
   To pay; to satisfy or appease. [Obs.] --Sir P. Sidney.
   [1913 Webster]