Fanqie () is a method in traditional Chinese lexicography to indicate the pronunciation of a monosyllabic character by using two other characters, one with the same initial consonant as the desired syllable and one with the same rest of the syllable (the final).
The method was introduced in the 3rd century AD and used in dictionaries and commentaries on the classics until the early 20th century.
Early dictionaries such as the Erya (3rd century BC) indicated the pronunciation of a character by the dúruò (讀若, "read as") method, giving another character with the same pronunciation. The introduction of Buddhism to China around the 1st century brought Indian phonetic knowledge, which may have inspired the idea of fanqie. According to the 6th-century scholar Yan Zhitui, fanqie were first used by Sun Yan (孫炎), of the state of Wei during the Three Kingdoms period (220–280 AD), in his Erya Yinyi (爾雅音義, "Sounds and Meanings of Erya"). However, earlier examples have been found in the late-2nd-century works of Fu Qian and Ying Shao.
The oldest extant sources of significant bodies of fanqie are fragments of the original Yupian (544 AD) found in Japan and the Jingdian Shiwen, a commentary on the classics that was written in 583 AD. The method was used throughout the Qieyun, a Chinese rhyme dictionary published in 601 AD during the Sui dynasty. When Classical Chinese poetry flowered during the Tang dynasty, the Qieyun became the authoritative source for literary pronunciations. Several revisions and enlargements were produced, the most important of which was the Guangyun (1007–1008). Even after the more sophisticated rime table analysis was developed, fanqie continued to be used in dictionaries, including the voluminous Kangxi Dictionary, published in 1716, and the Ciyuan and Cihai of the 1930s.
During the Qing dynasty, some bilingual Chinese-Manchu dictionaries had the Manchu words phonetically transcribed with Chinese characters.