The definition of a haiku is a Japanese verse poem of unrhymed lines which are written in a structure of 5 syllables for first line, 7 syllables for second line, then 5 syllables for third line.(noun)
An example of a haiku is a short poem about nature.
See haiku in Webster's New World College Dictionary
See haiku in American Heritage Dictionary 4
noun pl. haiku haiku also hai·kus
Origin: : hai, amusement (from Middle Chinese bəij, pha·j)
Origin: + ku, sentence (from Middle Chinese kuəh).
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