noun, noun which may take the genitive case particle 'no'
different kind; another sort; separate item; another approach; different means
Refers to something of a different type, category, or method; often used when contrasting with a previously mentioned option or when suggesting an alternative.
この問題は別口の解決策が必要だ。
This problem requires a different kind of solution.
彼は別口の仕事も引き受
He also took on another sort of work.
noun
Specifically a separate bank account or financial account, distinct from other accounts.
貯金用に別口の口座を開いた。
I opened a separate account for savings.