Answer:
Gainsay:
1. to deny, dispute, or contradict.
2: to speak or act against; oppose.
From: http:/dictionary.reference.com/browse/gainsay
No one ventured to gainsay the missionary, whose excited tone contrasted curiously with his naturally calm visage.
From: Around the World in 80 Days, by Jules Verne
Read the sentence in context at: http://www.classicreader.com/book/96/27/