三角

1. Origins, structure, and basic meaning

• Structure: Spelling: 三角. Reading: さんかく. Core meaning: triangle.
• Basic usage: Representative examples: 紙を三角に折って、しおりを作った / 地図の三角の印が集合場所を示している.

2. Common pitfalls and similar expressions

• Shape and symbol
  • 三角に折る means folding something into a triangular shape, while 三角の印 is a triangle-shaped symbol. The word does not have to name a separate geometric object.