Tanka (短歌 "short poem"?) is a genre of classical Japanese poetry and one of the major genres of Japanese literature.
Originally, in the time of the Man'yōshū (latter half of the eighth century AD), the term tanka was used to distinguish "short poems" from the longer chōka (長歌?, "long poems"). In the ninth and tenth centuries, however, notably with the compilation of the Kokinshū, the short poem became the dominant form of poetry in Japan, and the originally general word waka became the standard name for this form. Japanese poet and critic Masaoka Shiki revived the term tanka in the early twentieth century for his statement that waka should be renewed and modernized.Haiku is also a term of his invention, used for his revision of standalone hokku, with the same idea.
Tanka consist of five units (often treated as separate lines when romanized or translated) usually with the following pattern of on:
The 5-7-5 is called the kami-no-ku (上の句 "upper phrase"?), and the 7-7 is called the shimo-no-ku (下の句 "lower phrase"?).