[1] : The Collaborative International Dictionary of English v.0.48

gainsay \gain`say"\ ? or ?; 277, v. t. imp.  p. p.
   gainsaid ? or ?; p. pr.  vb. n. gainsaying. oe.
   geinseien, ageinseien. see again, and say to utter.
   to contradict; to deny; to controvert; to dispute; to forbid.
   1913 webster

         i will give you a mouth and wisdom which all your
         adversaries shall not be able to gainsay nor resist.
                                                  --luke xxi.
                                                  15.
   1913 webster

         the just gods gainsay
         that any drop thou borrow'dst from thy mother,
         my sacred aunt, should by my mortal sword
         be drained.                              --shak.
   1913 webster
see also:
gainsaid gainsaying again say 

Gainsaying >> G Words
Gainsaying, definition of term: Gainsaying
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