verb

There is no doubt that their work makes a useful contribution, but it does not provide enough evidence to gainsay the conclusions of earlier scholars.

“And there was something childlike about Griffith, too, even in his Matlock days, as a deceptively sharp ‘simple country lawyer,’ a big-kid boyishness that did not mask his intelligence or gainsay his authority.” — From an obituary for Andy Griffith in the Post & Courier (Charleston, South Carolina), July 7, 2012

You might have trouble figuring out “gainsay” if you’re thinking of our modern “gain” plus “say.” It should help to know that the “gain-” part is actually related to “against”—specifically the Old English word for “against”: “gēan-.” From that came Middle English “gain-,” which was joined with “sayen” (“say”) to form “gainsayen,” the Middle English predecessor of “gainsay.” So when you see “gainsay,” think “say against” — that is, “deny” or “contradict.”

From Merriam-Webster Online at www.Merriam-Webster.com.