To approach or move towards someone or something. She saw him come up to her with a smile.
To be mentioned or discussed. The topic of climate change will come up in the meeting.
To happen or occur unexpectedly. I had to leave early because something urgent came up.
To rise to the surface or become visible. The sun comes up over the horizon at dawn.
To be promoted or advance in position. He came up through the ranks to become the manager.