1. To dismiss someone from a job: 解雇する (kaiko suru) or クビにする (kubi ni suru)
* 解雇する is the more formal and polite way to say "dismiss" someone, and is often used by management or HR.
* クビにする is a more informal way to say "dismiss" someone and is often used by individuals.
2. To dismiss a thought or idea: 却下する (kyakka suru)
3. To dismiss a court case: 棄却する (kiketsu suru)
4. To dismiss a person or request: 断る (kotowaru) or けん制する (kensei suru)
* 断る is the more polite way to say "dismiss" someone or a request. It is often used when you do not want to do something or cannot help someone.
* けん制する is a more direct way to say "dismiss" someone or a request. It can be used when you want to make it clear that you are not interested in what the person has to say or do.