Simple past tense and past participle of gainsay.(verb)
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Use "gainsaid" in a sentence
"Did you know that MLK used the word gainsaid actually "gainsaying" in his Letter From a Birmingham Jail?"
"Ann's suggestion that the use of "gainsaid" in Brennan's opinion was "sheer pretension, a modern person's idea of how to sound like you came from the 19th century," has a little pretense to it as well."
"But what's this "sense of revulsion" that has come over Ann, just from a chance encounter with "gainsaid"?"