standard language; standard variety
Refers to the codified standard form of a language used in official, educational, and media contexts. In Japanese contexts, it often specifically means the Tokyo-based standard Japanese.
学校では標準語を使うように指導される。
At school, students are instructed to use standard language.
standard Japanese
When the context is clearly about Japanese, 標準語 is understood as the Tokyo-based standard Japanese, as opposed to regional dialects.
彼は関西弁ではなく標準語で話した。
He spoke in standard Japanese, not Kansai dialect.
She never uses dialect and always speaks standard Japanese.
The teacher corrected the dialect sentence into standard Japanese.
The teacher explained the grammar in standard Japanese.
This book prints the dialect dialogue translated into standard Japanese.