noun which may take the genitive case particle 'no'
separate; different; another; discrete
Used as a no-adjective to emphasize that two or more things are distinct, independent, or not the same. Often contrasts with 同一 (same/identical).
この問題は前のものとは別個に扱うべきだ。
This issue should be handled separately from the previous one.
彼らは別個の会社を経営している。
They run separate companies.