n. One who gainsays, contradicts, or denies. “To convince the gainsayers.” Tit. i. 9. [ 1913 Webster ]

v. t. [ imp. & p. p. Gainsaid 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 ]