Iroha Jiruishō

The Iroha Jiruishō (色葉字類抄 or 伊呂波字類抄^?, "Characters classified in iroha order and annotated") is a 12th-century Japanese dictionary of Kanji ("Chinese characters"). It was the first Heian Period dictionary to collate characters by pronunciation (in the iroha order) rather than by logographic radical (like the Tenrei Banshō Meigi) or word meaning (Wamyō Ruijushō).

The Iroha Jiruishō has a complex history (see Okimori 1996:8-11) involving editions of two, three, and ten fascicles (kan "scroll; volume"). The original 2-fascicle edition was compiled by an unknown editor in late Heian era circa 1144-1165 CE. This was followed by a 3-fascicle edition by Tachibana Tadakane (橘忠兼) circa 1177-1188. Finally, at the start of the Kamakura Period, another anonymous editor compiled the expanded 10-fascicle edition, entitled 伊呂波字類抄 (with Iroha written 伊呂波 instead of 色葉).

The main character entries are annotated with katakana to indicate both on'yomi Sino-Japanese borrowings and kun'yomi native Japanese pronunciations. The Iroha Jiruishō orthography shows that 12th-century Japanese continued to phonetically distinguish voiceless and voiced sounds, but the distinction between /zi/ and /di/, /zu/ and /du/, and /eu/ and /ou/ was being lost. These entry words typify the Japanized version of classical Chinese known as hentai Kanbun (変体漢文 "anomalous Chinese writing", see Azuma Kagami) or Wakan konkōbun (和漢混交文 "mixed Japanese and Chinese writing"). This is a bilingual dictionary for looking up Chinese characters in terms of their Japanese pronunciation, and not a true Japanese language dictionary.

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