The characters combine literally to mean “big character report,” a name that perfectly describes its form and function: a publicly posted report written in large-sized Chinese characters.
The 大字报 is a powerful symbol of a specific and chaotic period in modern Chinese history. Its significance is rooted in the political philosophy of “mass-line politics” promoted by Mao Zedong, which ostensibly empowered the masses to criticize those in power. During the Cultural Revolution, Mao's endorsement of a 大字报 at Peking University in 1966 effectively lit the fuse for nationwide turmoil. It became the primary medium for Red Guards and revolutionary factions to denounce teachers, intellectuals, officials, and anyone deemed a “counter-revolutionary.” These posters could ruin careers, destroy families, and lead to violent “struggle sessions” (批斗, pīdòu) and imprisonment. They created an atmosphere of fear, suspicion, and public humiliation, where personal grievances could be weaponized under the guise of political righteousness. Comparison to Western Concepts: A 大字报 is far more intense than a simple “protest sign” or “open letter.” A closer, though imperfect, modern analogy would be a “call-out post” or a “cancel culture” campaign on social media. Both involve public accusations intended to generate widespread condemnation and inflict reputational damage. However, the crucial difference lies in the context: a 大字报 during the Cultural Revolution was backed by state power and could have immediate, life-threatening physical consequences, whereas a social media campaign, while damaging, operates outside of formal state authority and rarely leads to physical violence sanctioned by the government.
In contemporary China, you will almost never see a physical 大字报 in the historical sense. The term has evolved to become almost entirely figurative.
The term serves as a cultural shorthand, instantly invoking images of irrational anger, public humiliation, and political chaos.