辞書

Etymology 1
A repurposing of older term, based on a reanalysis of the constituent characters +. Influenced by 🇨🇬-derived term, wherein the character expresses the meaning  from  , instead of the meaning  or  from 🇨🇬. Note that both of these older character forms were later conflated in both and 🇨🇬 into the simplified version 辞, with the  meaning becoming dominant in 🇨🇬.

First appearance in Japanese with the 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.

Compare modern 🇨🇬, possibly reborrowed from or otherwise influenced by the Japanese.

Noun

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

Etymology 2
From compound.

Noun

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

Etymology 3
The of jisho above. Most common from the Heian through the Muromachi periods.

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

Noun

 * 1)  a letter of resignation