Cí (pronounced [tsʰǐ]; Chinese: 詞), also known as chángduǎnjù (長短句; 长短句; 'lines of irregular lengths') and shīyú (詩餘; 诗馀; 'the poetry besides Shi'), is a type of lyric poetry in the tradition of Classical Chinese poetry that also draws upon folk traditions. Cí, also known as "song lyrics,[1][2]" use various poetic meters derived from a base set of fixed pattern forms, using fixed-rhythm, fixed-tone, and line-lengths varying according that of the model examples. The rhythmic and tonal pattern of the cí are based upon certain, definitive musical song tunes (cípái), and in many cases the name of the musical tune is given in the title of a cí piece, in a form such as "after (the tune of)...."[3][4]
Typically, the number of characters in each line and the arrangement of tones were determined by one of around 800 set patterns, each associated with a particular title, called cípái (詞牌). Originally, they were written to be sung to a tune of that title, with a set rhythm, rhyme, and tempo. Therefore, the title may have nothing to do with its content. Indeed, several cí often shared the same title. The titles did not refer to the content, but rather their shared rhythmic and tonal patterns. Some cí have a "subtitle" or a commentary, sometimes as long as a paragraph, indicating the content. Sometimes, for the sake of clarity, a cí is listed under its title, followed by its first line.[5]