Holy fucking shit, here’s some Monday morning knowledge:
Source: Wikipedia, which I will blindly put faith in:
Haiku (俳句, haikai verse)
listen (help·info), plural haiku, is a form of Japanese poetry, consisting of 17 moras (or on), in three phrases of 5, 7, and 5 moras respectively.[1] Although haiku are often stated to have 17 syllables,[2] this is inaccurate as syllables and moras are not the same. Haiku typically contain a kigo (seasonal reference), and a kireji (cutting word).
Mora (plural moras or morae) is a unit of sound used in phonology that determines syllable weight (which in turn determines stress or timing) in some languages. As with many technical linguistics terms, the exact definition of mora varies. Perhaps the most succinct working definition was provided by the American linguist James D. McCawley in 1968: a mora is “Something of which a long syllable consists of two and a short syllable consists of one.”
