Describes something that is not primary or main, often used in contrast with 一次的 (primary). Common in technical, academic, or formal contexts.
この問題は二次的なものだ。
This issue is secondary.
二次
We need to investigate secondary causes.
二次的 is a more formal, analytical way to say something is secondary, whereas 二の次 is the everyday idiom used in casual speech.
derivative work
Compound of 二次 (にじ, 'secondary') + 的 (てき, '-like, -al'). 二次 is itself from 二 (に, 'two') + 次 (じ, 'order, next').