When the eye takes in a human figure from behind, the gaze is drawn first from the curve of the waist down to the buttocks.

Buttocks (Japanese: お尻, oshiri) is the colloquial Japanese term for the body part formed by the gluteus maximus, medius, and minimus over the rear of the pelvis, with a layer of subcutaneous fat above. Anatomy calls it the gluteal region (denbu), the formal name used in medicine and kinesiology. The everyday oshiri settled in the early modern era as a euphemism prefixed with the polite “o-.”

Overview

The buttocks are one of the body’s regions of relatively thick fat and muscle, and the development of the gluteus maximus to support bipedal gait is regarded as a feature of human evolution. As a sex difference, the female buttocks often take a characteristic roundness from the distribution of subcutaneous fat combined with pelvic width, repeatedly thematised as an object of visual aesthetics in art, literature, and sexual representation.

As an erogenous zone, the surface skin of the buttocks is itself poor in direct sensation, but as a continuous stimulation region with the adjacent anus, perineum, and sacrum it participates indirectly in sexual response. It becomes an object of sexual attention in modes from striking to caressing to visual appreciation. Derived concepts circulate in parallel: beautiful hips (evaluating form), “peach hips” (likening youthful roundness to a peach), “huge hips” (emphasising size), and “easy-birth type” (an idiom for pelvic width).

Etymology

Shiri is one of the basic words of ancient Japanese, attested in the Man’yōshū. The kanji 尻 derives from a pictograph of the rear of the body and was used as a body-part name in the Chinese classics. The polite form oshiri spread with the development of euphemism for body parts in the early modern period, alongside o-naka (belly), o-kao (face), and others. In scholarly and medical contexts the Sino-Japanese denbu is used. English buttocks derives from Old English buttuc (“end,” “edge”); hip is a separate word for the lower-back region as a whole.

History and cultural position

The ancient Greek statue Aphrodite Kallipygos (“Aphrodite of the beautiful buttocks”), dated to around the 3rd century BCE, is one of the oldest sculptural remains thematising the aesthetic value of the female buttocks; kallipygos itself was an established aesthetic word for the body. In Japan, the picture scrolls of the Heian period and early-modern shunga continuously used rear-entry compositions and arrangements emphasising the buttocks; in the shunga of Harunobu, Utamaro, and Hokusai, the curve from waist to buttocks was an element showing the artist’s skill.

From the late 19th to the early 20th century, the Western vogue for the corset and bustle (a skirt structure swelling the buttocks) institutionalised visual emphasis of the lower back and buttocks. In postwar Japan, the spread of Western dress gradually settled fashion emphasising the line of the buttocks (tight skirts, jeans, body-conscious suits), with the late-1980s bodikon vogue as one peak. In adult representation, an independent genre thematising the buttocks formed from the 1990s, developing across media: the “huge hips” and “beautiful hips” divisions of AV genre, hip-fetish character types in manga and anime, and rear-view features in photo collections. The English-language vogue for booty and bootylicious via hip-hop culture (2000s) influenced Japan as a global current of body aesthetics.

Sub-forms

A visual-appreciation type emphasises the curve of the buttocks in rear views, crouching, and all-fours poses, including appreciation with shape emphasised by underwear, swimwear, or tight skirts. A contact type includes caressing, kneading, and striking (spanking); spanking is also a core gesture of SM culture, with practices ranging from light striking to full training. A positional involvement covers rear-entry, cowgirl, and standing positions, where the form and motion of the buttocks are emphasised visually and tactilely; the rear-entry position especially places the buttocks at the centre of the field of view and has high affinity with buttock fetishism.

Reception psychology

On the origin of sexual interest in the buttocks, evolutionary explanations cite a function as a visual indicator of fertility (hip width, fat distribution) tied to bipedal gait. From an anthropological view, the concrete form of buttock aesthetics (the ideal size and shape) varies greatly by culture and period, so biological explanation alone cannot exhaust the particulars of individual cultures. A noted feature of buttock aesthetics in Japan is that pre-modern evaluation centred on the hips as a whole, and the gaze that carves out the buttocks as an independent aesthetic object strengthened from the modern era; the spread of Western dress, the development of photographic media, and the subdivision of adult representation precipitated the buttocks as a distinct category of preference.

Related terms

• Beautiful hips
• Spanking
• Rear-entry position
• Anus
• Cowgirl position
• Shunga
• Bodikon
• SM culture
• Hips and lower back