come online (third-person singular simple present comes online, present participle coming online, simple past came online, past participle come online)
- (idiomatic) To enter service or become active.
- It will be some time before the new factory comes online, and until then we can't fulfill demand.
- (idiomatic) To login to an Internet communication system, such as an instant messenger, online game or forum.
- Come online later; I want to talk to you.