The Chinese idiom "无稽之谈" is formed through a classical grammatical structure where "无稽" (wú jī), meaning "unfounded" or "without proof" (literally "without examination"), modifies "谈" (tán), meaning "talk" or "discourse," with the possessive marker "之" (zhī) linking them to create "talk that is unfounded." Historically rooted in the phrase "无稽之言" from the ancient *Book of Documents*, it figuratively condemns any statement as baseless, absurd, or not worth investigating, thus serving as a powerful refutation of ridiculous claims.