to defy public opinion by doing something everyone knows is wrong; to flagrantly act against the common sense of right and wrong despite certain criticism

(literary) a fault or error; a wrongdoing; used almost exclusively in the idiom [[冒天下之大不韪|冒天下之大不韙|mao4 tian1 xia4 zhi1 da4 bu4 wei3]]

(idiom) to act in defiance of general opinion or face public outcry; to disregard universal condemnation

William A.P. Martin (1827-1916), American missionary who lived in China for 62 years and helped found several colleges, including serving as the first president of the Imperial University of Peking.

a great error or a heinous crime; a serious offense against what is right

to defy the common judgment of the world or to act in the face of universal disapproval