上位 じょうい互換 ごかん
jōigokan

Noun
no-Adjective

1. downward compatible; backward compatible; compatible with input or components intended for lower tier or older systems, versions, etc. — explanation

Related to 後方互換
Noun
no-Adjective

2. upward compatible; forward compatible; compatible with input or components intended for higher tier or later systems, versions, etc. — explanation

Noun
no-Adjective

3. providing the same function while being more effective (esp. in games)

Slang