'Shī yún' literally means 'the poem says' and functions as a classical literary conjunction used to introduce a quoted line from a poem—especially from the Shījīng (Classic of Poetry) or other canonical verse. The character 诗 (shī) means 'poem' or 'poetry', while 云 (yún) is an archaic verb meaning 'to say' or 'to state'. Together, they form a fixed, formal expression that signals the speaker is citing poetic authority to support or illustrate a point.

This phrase appears frequently in classical Chinese texts, scholarly commentary, and formal speeches or essays drawing on traditional wisdom. It carries a respectful, erudite tone and is rarely used in casual speech. Modern writers may employ it deliberately for rhetorical elegance or cultural resonance—often when referencing nature imagery, moral principles, or seasonal themes, which aligns with its frequent use in poems about plants, landscapes, and agricultural cycles.