noun, noun or participle which takes 'suru', transitive verb
Used when an organization or person takes the lead in planning and running an event, conference, or competition. Often implies official responsibility and public-facing role.
市が毎年この祭りを主催している。
The city organizes this festival every year.
学会を主催する準備で忙しい。
I'm busy preparing to host the academic conference.