gainsay

 
Pronunciation: /geɪnˈseɪ/

verb (past and past participle gainsaid /-ˈsed/)

[with object, with negative] formal
  • deny or contradict (a fact or statement): the impact of the railways cannot be gainsaid
  • speak against or oppose (someone): none could gainsay her

Derivatives

gainsayer

noun

Origin:

Middle English: from obsolete gain- 'against' + say