上じょう位い互ご換かん

noun which may take the genitive case particle 'no', noun

backward compatible; downward compatible

Technical term for compatibility with older or lower-tier systems, versions, or components. Often used in IT and gaming contexts.

See also: 後方互換

• このソフトは上じょう位い互ご換かんなので、古ふるいファイルも開あけます。

  This software is backward compatible, so it can open old files.

noun which may take the genitive case particle 'no', noun

upward compatible; forward compatible

Often considered a misuse; the correct technical term for compatibility with newer or higher-tier systems is 前方互換 or 上位互換性. Still encountered in some contexts.

• この規き格かくは上じょう位い互ご換かんをうたっているが、実じっ際さいには前ぜん方ぽう互ご換かんの意い味みで使つかわれている。

  This standard claims to be upward compatible, but it is actually used to mean forward compatible.

noun which may take the genitive case particle 'no', noun

strictly better; superior version

Slang, especially in gaming, for something that provides the same function but is more effective or powerful. Often used in comparisons like 'A is a 上位互換 of B'.

• この新しんキャラは前まえのキャラの上じょう位い互ご換かんだ。

  This new character is a strictly better version of the previous one.