The upper stone of a stone tea-mill rotates horizontally on top of the lower stone. The Edo-period erotic-book artists connected this everyday-object motion to the hip-rotation of the receiving partner in a particular sexual configuration. The naming-economy of the era was open in a way that ours is not.

Chausu (Japanese: 茶臼, chausu, “tea-mill”) is the Edo-period name for the sexual configuration in which the inserting partner takes a supine position and the receiving partner sits astride the inserting partner’s hips, facing forward. The configuration is the predecessor of the contemporary kijoui (cowgirl) position-category. The name comes from the stone tea-mill (chausu, 茶臼), a household implement for grinding tea-leaves into powder; the rotating motion of the upper stone over the lower stone is the metaphorical source for the position-name. The configuration appears as one of the principal positions in the forty-eight-positions (shijūhatte) classification developed by Hishikawa Moronobu and subsequent Edo-period erotic-book artists from the 1670s onward. Contemporary Japanese vocabulary uses the position-name chausu with a more classical-literary register than the more common kijoui.

Overview

The chausu configuration places the receiving partner astride the inserting partner. The receiving partner (in the traditional configuration, female) supports the body on knees or feet on either side of the inserting partner’s hips, and the inserting partner (traditionally male) lies supine below.

The configuration has two principal variants. In the kneeling-squat variant (sonkyo-gata), the receiving partner kneels on both knees on the bedding. In the standing-squat variant, the receiving partner supports the body on the soles of the feet, in a deep squat posture. The forty-eight-positions canon identifies the chausu primarily as the kneeling-squat variant.

The name connects to the tea-mill (chausu) through structural analogy. The Japanese stone tea-mill consists of two stones, with the upper stone rotating horizontally over the lower stone to grind tea-leaves between them. The Edo erotic-book artists noticed the rotational hip-motion of the receiving partner in this configuration and connected it to the rotational motion of the upper stone over the lower. The Edo-period erotic-book corpus features the chausu as one of the two principal positions alongside the honte (basic missionary), and the configuration appears across the shunga works of Hishikawa Moronobu, Suzuki Harunobu, Katsushika Hokusai, and Kitagawa Utamaro.

Etymology

Chausu (茶臼) is the Japanese name for the stone tea-mill used to produce powdered matcha-tea. The implement consists of two cylindrical stones (the upper and lower stones) fitted together so that the upper stone rotates over the lower stone, with tea-leaves fed through a central hole. The rotational grinding motion was a familiar everyday sight in Edo-period Japan, particularly in tea-producing households and tea-related establishments.

The Nihon Kokugo Daijiten (the principal Japanese-language reference dictionary) identifies the Hishikawa Moronobu forty-eight-positions documents as the earliest source for the sexual-position usage of chausu. The etymological-analytical consensus locates the source-domain in the rotational hip-motion of the position, though some folkloric-historical research finds the source more specifically in “the feeling-of-resistance of grinding tea” — the tactile sensation of the tea-mill operator — as the motion-quality with which the receiving partner’s hip motion is compared.

Chausu circulated in the Edo period in verbal-noun constructions such as chausu o hiku (“to grind the tea-mill”) and chausu ni noru (“to mount the tea-mill”), with the sexual-vocabulary versatility characteristic of euphemistic vocabulary. From the Meiji-period (post-1868) integration of Western sex-education and medical vocabulary, the academic usage of chausu retreated under pressure from the Western-derived terminology (“face-to-face superior position,” “woman-on-top position,” etc.), but the term has survived in erotic-vernacular and popular-literature contexts.

English-language vocabulary has no direct equivalent. The modern English cowgirl position (with its Western-cinematic woman-rider connotation) and woman on top are the standard near-equivalents. The Chinese 女上位 (nǚ shàng wèi) is the general-vocabulary term and does not employ a tea-mill-style implement-analogy.

Historical record

Position in the forty-eight-positions canon

The forty-eight-positions (shijūhatte) is the Edo-period erotic-book classification system for sexual configurations, with its origin in Hishikawa Moronobu’s 1670s erotic-book corpus Koi no Mutsugoto Shijūhatte (Forty-Eight Hands of Love-Whispers). The “forty-eight” of the name derives by analogy from the number of formalised techniques in classical sumo wrestling (the canonical forty-eight throws), giving the system a parodic-classical register that compares sexual configurations to sumo technique-categories.

Within this system, the chausu occupies the central representative position for the cowgirl-class (mounted, woman-on-top) configurations. The derivative variants of the chausu are numerous, including i-chausu (居茶臼, “seated tea-mill”; the seated-face-to-face variant), chausu-nobashi (茶臼のばし, “extended tea-mill”; the variant in which the receiving partner leans forward and extends the legs), matsuba-kuzushi (松葉崩し, “pine-needle-disturbance”; the variant with crossed-leg configuration), ikada-chausu (筏茶臼, “raft tea-mill”), and shigure-chausu (時雨茶臼, “drizzle tea-mill”), among others. The Edo-period naming-tradition’s tendency to give discrete names to fine-grained variations of a single position-class can be read as a distant ancestor of the genre-subdivision tendencies of contemporary Japanese cultural production.

The frequency of the chausu in Edo-period shunga is partly explained by compositional considerations. The configuration places the receiving partner’s body in the visual foreground, allowing the picture-plane to depict the details of the disarranged hair-style, the fallen jūban under-kimono, the displaced obi belt, and the back-view of the upper body in the case of the reverse-chausu (haimen-chausu) variant. The shunga depiction of the female body achieved its most ornate compositional treatment in the chausu configuration.

Modern reception

The Meiji-period integration of Western sex-education and medical vocabulary brought “face-to-face superior position,” “woman-on-top position,” and kijōi (騎乗位) into the academic-medical register, displacing chausu into the erotic-vernacular and popular-culture register. By the postwar period, contemporary sex-advice publications and AV-industry vocabulary used kijōi as the standard term, with chausu retreating into a classical-literary register.

The contemporary revival of interest in Edo culture and in the forty-eight-positions canon has brought chausu back into circulation. Nagai Yoshio’s Edo Sex Vocabulary Dictionary (2014) and Shirakura Yoshihiko’s Shunga and the Dosojin (2010) are central works of the contemporary scholarly re-evaluation of the forty-eight-positions naming-tradition.

Variants

I-chausu (seated tea-mill)

In the i-chausu variant, both partners take seated configurations and the receiving partner sits astride the inserting partner’s hips. The inserting partner’s arms wrap around the receiving partner’s back, producing the largest body-contact area among the chausu-family variants. The configuration is depicted with high frequency in Edo erotic-book imagery as a couples-intimacy scene, with the conventional description “the intimately-bonded i-chausu.”

Chausu-nobashi (extended tea-mill)

In the chausu-nobashi variant, the receiving partner leans the upper body forward and extends the legs backward, draping the upper body on the inserting partner. The configuration brings the partners’ faces close together and is documented in Edo erotic books as a closeness-of-affection variant.

Ikada-chausu and shigure-chausu

The ikada-chausu (raft tea-mill) places the receiving partner with both legs extended on the bedding in a raft-like posture; the shigure-chausu (drizzle tea-mill) describes a variant with rhythmic up-and-down motion repeated in a particular drizzle-like pattern. The descriptive details vary between erotic-book sources, and the boundaries of these named variants are not consistently drawn across the corpus.

Haimen-chausu (reverse tea-mill)

In the haimen-chausu (背面茶臼, “back-facing tea-mill”) variant, the receiving partner faces toward the inserting partner’s feet rather than the head. The configuration corresponds to the contemporary haimen-kijoui (reverse-cowgirl). In Edo erotic-book vocabulary the variant is also labelled sakasa-chausu (逆茶臼, “reversed tea-mill”) or ura-chausu (裏茶臼, “back-side tea-mill”).

Visual expression in shunga

The chausu family of configurations had a structural compositional advantage in Edo-period shunga: it placed the female figure in the foreground of the composition, allowing the picture-plane to feature the female-body-and-clothing details. Hishikawa Moronobu and subsequent Edo-period artists exhibited a sustained focus on the chausu compositional configuration for this reason.

Specific compositional devices recur in shunga chausu depictions: the fallen obi and disarranged jūban sliding toward the foreground of the picture-plane; the disordered hair of the receiving partner falling from the nape of the neck down the back; the upward-looking gaze of the inserting partner placed in the lower section of the picture-plane, with the forward-facing expression of the receiving partner placed in the upper-centre. The chausu compositions function as the ideal “performance-stage” of the Edo erotic-book artists, placing the female figure at the visual centre of the composition.

The Hokusai Manpuku Wagōjin (萬福和合神), the Utamaro Utamakura (歌まくら), and the Suzuki Harunobu shunga corpus all include chausu-family compositions as core works. The high frequency of chausu compositions in Edo-period shunga prefigures the structurally-comparable centrality of the cowgirl/kijoui position in contemporary Japanese AV-industry composition.

Position in contemporary use

In contemporary Japanese ordinary-language contexts, chausu is used as a classical-archaic synonym for kijoui. The AV-industry genre-tag-and-marketing vocabulary uses the contemporary kijoui, with chausu appearing in the context of historical-Edo-setting productions, period-drama productions, and historically-themed erotic manga.

The historical-setting works in dōjinshi and adult-manga production occasionally incorporate the chausu name as part of an Edo-culture-reference vocabulary set. With the contemporary academic re-evaluation of the forty-eight-positions canon, the discrete position-names (chausu, matsuba-kuzushi, shigarami, honte) have an increasing available register for re-deployment in contemporary production.

Related Terms

• Kijoui (woman-on-top)
• Haimen-kijoui (reverse-cowgirl)
• Matsuba-kuzushi
• Shunga
• Ukiyo-e
• Forty-eight positions (shijūhatte)
• Hishikawa Moronobu
• Katsushika Hokusai
• Kitagawa Utamaro