せんしゅう専修senshuu
1.

The process of dedicating oneself to studying or mastering a specific subject or field, often with a focus such as a major in university education.

2.

The practice of intensively engaging in a particular method or discipline, especially in contexts that emphasize deep knowledge or expertise in one area.

3.

A term describing the exclusive commitment to one particular practice or technique, often used in religious contexts to denote adherence to a single spiritual method.