An 18th and 19th century Edo 江戸 merchant class ideal implying sophisticated knowledge, discernment, and culture. Eventually the term was applied to someone who possessed *iki いき, but originally the two ideas were somewhat distinct. Where iki was an aesthetic ideal implying a chic sense of beauty, tsū was more cerebral, connoting a "fashionable intellect." The possessor of tsū, a tsūjin 通人 or daitsū 大通, for example, not only knew his way around the pleasure quarters, but was someone who understood the essence of the "floating world" ukiyo 浮世.
The tsūjin was the antithesis of the yabo 野暮 or bumpkin who lacked both outer refinement and inner understanding, a man with neither culture nor discernment. One who had tsū was adept at ugachi 穿ち, the witty demonstration of a superior intellect, and share 洒落, the parodistic manipulation of language and image.
The ideal of tsū found expression in both literature and art. The concept of tsū, with its ramifications of wit and parody, exerted a great influence on *ukiyo-e 浮世絵 prints and paintings, particularly the often satiric inversions of old themes found in *mitate-e 見立絵. The prototypical tsūjin was the artist and writer Okumura Masanobu 奥村政信 (1761-1816) who may be said to have introduced the sophisticated intelligence of tsū into ukiyo-e.