The Chinese idiom **欣喜若狂 (xīnxǐ ruò kuáng)** is formed through a classical four-character metaphorical structure, where the first two characters **"欣喜"** directly denote "joyful and delighted," establishing the core emotion of happiness. The latter two characters **"若狂"** function as a simile, meaning "as if mad" or "like one is crazed." When combined, the phrase creates a vivid figurative meaning: the joy is so intense and overwhelming that it borders on a state of ecstatic madness, thus perfectly encapsulating the concept of being "wild with joy" or "elated."