n. pl. haiku also hai·kus
a. A Japanese lyric verse form having three unrhymed lines of five, seven, and five morae, traditionally invoking an aspect of nature or the seasons.
b. A verse form in another language modeled on the Japanese haiku, typically counting syllables instead of morae.
2. A poem written in this form.
[Japanese : hai, amusement (from Middle Chinese pɦaːj) + ku, phrase (from Middle Chinese kyə̆`, sentence; also the source of Mandarin jù).]
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