The word "楷书" is formed from two characters: "楷" is a phono-semantic compound where "木" (wood) serves as the semantic component, implying something standard or model, and "皆" provides the phonetic sound; "书" is a simplified character derived from a pictograph of a hand holding a brush, meaning writing. Combined, "楷" modifies "书" to denote "regular script", a standardized style of Chinese calligraphy.