The Collaborative International Dictionary of English v.0.48:

Astony \As*ton"y\, v. t. [imp. & p. p. Astonied; p. pr. & vb.
   n. Astonying. See Astone.]
   To stun; to bewilder; to astonish; to dismay. [Archaic]
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         The captain of the Helots . . . strake Palladius upon
         the side of his head, that he reeled astonied. --Sir P.
                                                  Sidney.
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         This sodeyn cas this man astonied so,
         That reed he wex, abayst, and al quaking. --Chaucer.
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