Haiku (俳句, haikai verse^?)  listen (help·info), plural haiku, is a very short form of Japanese poetry typically characterised by three qualities:

Modern Japanese gendai (現代) haiku are increasingly unlikely to follow the tradition of 17 on or to take nature as their subject, but the use of juxtaposition continues to be honoured in both traditional haiku and gendai. There is a common, although relatively recent, perception that the images juxtaposed must be directly observed everyday objects or occurrences.

In Japanese, haiku are traditionally printed in a single vertical line while haiku in English often appear in three lines to parallel the three phrases of Japanese haiku.

Previously called hokku, haiku was given its current name by the Japanese writer Masaoka Shiki at the end of the 19th century.