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An Encyclopaedia on Chinese History and Literature
Jian 牋 was a form of address used for individuals of very high rank, such as empresses and crown princes. It was less formal than a memorial (zou 奏, biao 表). Officially, jian addresses resembled memorials (biao).
The character was initially used for writing slips made of wood (not bamboo, for which the word jian 簡 was used). It is interchangeable with the character jian 箋 (but not, if this word means a commentary on a text). Other words for such addresses are jianbiao 牋表, jiandu 牋牘, jianji 牋記, jianjian 牋簡, jianqi 牋啓, jianxi 牋檄, jianzha 牋札/牋劄 or jianzou 牋奏.
Another meaning of the word jian was "private letter" (in the expression jianshu 牋書), and the third meaning was high-quality paper used for private letters. The expressions jianshu 牋疏 and zoujian 奏牋 were used to designate reports submitted to superior persons in the local and regional administration.