改訂（かいてい、kaiteい）
- revised edition

The Japanese word 改訂 （かい‐てい, *kaitei*） means "revision," "amendment," "update," or "revised edition." It refers to the act of making changes or corrections to something that already exists, such as a document, a book, a plan, or a system. The core idea is to improve or adjust something by adding new information, fixing errors, or making it more suitable for its current purpose. It often implies a significant change or improvement compared to a simple correction.

⚫︎ 教科書の改訂 Translation: Revision of a textbook ⚫︎ 契約書の改訂 Translation: Amendment of a contract ⚫︎ ソフトウェアの[改訂]版 Translation: Revised version of the software

⚫︎ 改訂 is used when discussing changes made to something that already exists, not the creation of something new. ⚫︎ It is appropriate for formal and informal contexts. ⚫︎ Often used in business, academic, and technical settings. ⚫︎ You can use it when talking about books, documents, laws, regulations, software, and more. ⚫︎ You can use different conjugations of 改訂 to form different tenses, for instance, 改訂する（*kaitei suru* - to revise), 改訂した（*kaitei shita* - revised), and [改訂]中（*kaitei-chuu* - under revision).

⚫︎ The standard writing is in Kanji: 改訂. ⚫︎ The reading is written in Hiragana: かい‐てい. ⚫︎ The okurigana (送りがな - the suffix hiragana) is always 訂.

⚫︎ 修正（しゅうせい, *shuusei*） - Correction, amendment (often less significant than [改訂]) ⚫︎ 変更（へんこう, *henkou*） - Change, alteration (a general term) ⚫︎ 見直し（みなおし, *minaoshi*） - Review, reconsideration ⚫︎ 改版（かいはん, *kaihan*） - Revision of a publication, edition ⚫︎ 更新（こうしん, *koushin*） - Update, renewal

⚫︎ The direct antonyms for 改訂 are not straightforward, as it's an action. However, you can consider words related to maintaining the original version, such as: ⚫︎ 変更なし（へんこうなし, *henkou nashi*） - No change ⚫︎ そのまま（*sonomama*） - As is, unchanged

この法律は、来年[改訂]される予定です。 ・Translation: This law is scheduled to be revised next year. ・Explanation: This sentence indicates that the law will undergo changes in the future, meaning 改訂.

[改訂]版の参考書を買いました。 ・Translation: I bought a revised edition of the reference book. ・Explanation: This implies that the reference book has undergone revisions and this is the new version, using 改訂.

The word 改訂 is composed of two Kanji: ⚫︎ 改 （かい, *kai*） - Meaning "to change," "to reform," "to correct." ⚫︎ 訂 （てい, *tei*） - Meaning "to revise," "to amend," "to correct," "to check". The combination of these characters creates the meaning of revising or amending something.