Explore each form from the oldest known stage to today.
Historical forms are not available yet. The current form is shown as a reference.
The kanji "凹" is a pictograph representing a concave or hollow shape. Its origin is classified as a pictographic character (象形文字), directly depicting the physical form of a depression or an indentation. The character's structure visually mimics a surface that curves inward, with the central element receding from the outer lines. This makes it one of the simplest and most direct visual representations in the Chinese script. Historically, the character "凹" is not found in the earliest Chinese scripts like oracle bone or bronze inscriptions. It is considered a later creation, emerging during the clerical script (隷書) period as writers sought characters to describe specific shapes. Along with its counterpart "凸" (convex), it functioned as a graphic symbol for abstract spatial concepts. The character was standardized in China and subsequently introduced to Japan, like the vast majority of kanji, through cultural exchange, most systematically during the Yamato period via Korean peninsular scholars and later directly from Tang China. It was incorporated into the Japanese writing system with its meaning and form intact. Linguistically, "凹" is categorized under the *kan-i* (漢音) reading "オウ" (ō) for its Sino-Japanese pronunciation, while its native Japanese *kun'yomi* is "くぼむ" (kubomu, to become hollow) or "へこむ" (hekomu, to be dented). A notable cultural aspect is its status as a *jitai* (字体) or "body shape" character; it is one of the few modern kanji whose structure is defined purely by its visual form rather than by phonetic or semantic components. This makes it an exception to the standard classification system of Chinese characters and a clear example of pictographic principles enduring in the modern lexicon.