Gojūon

The gojūon (五十音) is a Japanese ordering of kana. Gojū (五十) means "fifty," and on (音) means 'sound', so gojūon means 'fifty sound' ordering. Despite the name, it only contains 46 common sounds, plus two no longer in use. It is named such for the original 10 by 5 grid that the syllables fit in. (Note that such a grid does not include the syllabic n (ん), which was introduced long after the gojūon ordering was formed.)
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