From China Digital Space
空椅子 (kōng yǐzi): empty chair
Writer and dissident Liu Xiaobo, who was sentenced to an 11-year prison sentence for “inciting subversion of state power” in 2009, was awarded the 2010 Nobel Peace Prize. Unable to attend the award ceremony in Oslo due to his incarceration, the laureate was represented by his empty seat. Shortly thereafter, the term “empty chair” became a sensitive word in Chinese cyberspace.
Some bloggers who used the term online following the 2010 Nobel ceremony had their accounts blocked, and some who participated in a campaign to post images of empty chairs saw their posts censored—some accounts were even deleted for posting the image.