Historical kana usage

The historical kana orthography (, rekishi-teki kana-zukai, or "rekishi-teki kana-dukahi" in the old system^?), or old orthography (旧仮名遣, kyū kana-zukai, or "kiu kana-dukahi" in the old system^?), refers to the kana orthography (正仮名遣, sei kana-zukai^?) in general use until orthographic reforms after World War II; the current orthography was adopted by Cabinet order in 1946. By that point the historical orthography was no longer in accord with Japanese pronunciation. It differs from modern usage (Gendai kana-zukai) in the number of characters and the way those characters are used. There was considerable opposition to the official adoption of the current orthography, on the grounds that the historical orthography conveys meanings better, and some writers continued to use it for many years since.

The historical orthography is found in most Japanese dictionaries, such as Kōjien. In the current edition of the Kōjien, if the historical orthography is different from the modern spelling, the old spelling is printed in tiny katakana between the modern kana and kanji transcriptions of the word. Ellipses are used to save space when the historical and modern spellings are identical. Older editions of the Kōjien gave priority to the historical orthography.

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