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wallposter

American  
[wawl-poh-ster] / ˈwɔlˌpoʊ stər /

noun

  1. (in China) a usually lengthy notice, complaint, personal opinion, etc., handwritten in large characters and hung on walls in cities, as a means of communication and for criticizing or attacking government policy or politicians.


wallposter British  
/ ˈwɔːlˌpəʊstə /

noun

  1. (in China) a bulletin or political message painted in large characters on walls

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of wallposter

First recorded in 1965–70; wall + poster 1