Poetry Japanese formal poetry (which was generally referred to as "waka"), and was used more heavily to explore personal rather than public themes. By the tenth century, tanka had become the dominant form of Japanese poetry, to the point where the originally general term "waka" ("Japanese poetry") came to be used exclusively for tanka. Tanka are still widely written today. Haiku is a popular form of unrhymed Japanese poetry, which evolved in the 17th century from the "hokku", or opening verse of a renku. Generally written in a single vertical line, the haiku contains three sections totalling 17 "onji", structured in
Haiku the 5-7-5 pattern. Although the word ""on"" is sometimes translated as "syllable", one "on" is counted for a short syllable, two for an elongated vowel or doubled consonant, and one for an "n" at the end of a syllable. Thus, the word "haibun", though counted as two syllables in English, is counted as four "on" in Japanese (ha-i-bu-n); and the word ""on"" itself, which English-speakers would view as a single syllable, comprises two "on": the short vowel o and the . This is illustrated by the Issa haiku below, which contains 17 "on" but only 15 syllables. Conversely, some sounds,