理系

1. Origins, structure, and basic meaning

• Structure: 理系 (りけい) is a classificatory noun for the science and mathematics side of an educational track.
• Basic usage: 理系に進む presents the science track as the path chosen for study, while 理系の学生 modifies students by their academic field.

2. Common pitfalls and similar expressions

• Chosen track and field affiliation
  • 理系に is the educational path chosen before studying chemistry, while 理系の学生 identifies students already in that track. 理系 is not identical to one particular science subject.