微粒子

1. Origins, structure, and basic meaning

• Structure: 微粒子 (びりゅうし) is a compound noun for extremely small particles suspended in air or present in a material.
• Basic usage: 空気中の微粒子を測定する makes airborne particles the measured object, while 金属の微粒子が写る makes metal particles the subject appearing in a microscope image.

2. Common pitfalls and similar expressions

• Location versus material
  • 空気中の微粒子 identifies where the particles occur, whereas 金属の微粒子 identifies their material. Neither the air itself nor the microscope image is called a particle.