主要

1. Origins, structure, and basic meaning

• Structure: 主要 is read as しゅよう and is a na-adjective meaning main or principal among several elements.
• Basic usage: Central challenges appear in 主要な課題, while a principal route appears in 主要路線.

2. Common pitfalls and similar expressions

• Relative importance within a whole
  • Rather than judging quality, it identifies an element as central among the parts making up a whole.
• Difference from 重要
  • The comparison term means important in value or necessity, while this word focuses on being one of the central elements.