辞書

A repurposing of older term 辞書 (jisho, “letter of resignation”, see below), based on a reanalysis of the constituent characters 辞 (ji, “resignation, quitting; word”) + 書 (sho, “writing, record, document, book”). Influenced by Middle Chinese-derived term 辞典 (jiten, “dictionary”), wherein the 辞 character expresses the meaning word from Middle Chinese 辭／辞 (zi), instead of the meaning resignation or quitting from Middle Chinese 辤 (zi). Note that both of these older character forms were later conflated in both Japanese and Chinese into the simplified version 辞, with the word meaning becoming dominant in Chinese.

First appearance in Japanese with the dictionary sense might be the 1595 publication by the Jesuits of the 羅葡日辞書 (Ra-Ho-Nichi Jisho, “Latin-Portuguese-Japanese Dictionary”), alternate title Dictionarium Latino Lusitanicum, ac Iaponicum.[1]

Compare modern Mandarin 辭書／辞书 (císhū, “dictionary, lexicon”), possibly reborrowed from or otherwise influenced by the Japanese.

• (Tokyo) じ​しょ [jíꜜshò] (Atamadaka – [1])[2][3][4]
• IPA^(key): [d͡ʑiɕo̞]

辞(じ)書(しょ) • (jisho) 

1. a dictionary (publication that explains the meanings of an ordered list of words)

From Middle Chinese compound 辤書／辤书 (zi syo, literally “quit + writing”).

• (Tokyo) じ​しょ [jíꜜshò] (Atamadaka – [1])[2][3][4]
• IPA^(key): [d͡ʑiɕo̞]

辞(じ)書(しょ) • (jisho) 

1. a letter of resignation
2. a formal document of abdication when one emperor steps down and a new emperor ascends the throne

The 直音表記 (chokuon hyōki, literally “straight-sound spelling”) of jisho above. Most common from the Heian through the Muromachi periods.[5]

It is unclear if the pronunciation itself also shifted, or just the spelling.

• IPA^(key): [d͡ʑiso̞]

辞(じ)書(そ) • (jiso) 

1. (obsolete) a letter of resignation