open up to
1. To spread or unfold outward. As we came out of the mountain pass, the road opened up and the great plains lay before us.
2. To become open; to no longer be closed. The country's borders opened up again for the first time since the crisis. The box opened up all on its own while it played a pleasant little jingle.
3. To open something, as by removing a lid or other seal or means of closure. A noun or pronoun can be used between "open" and "up." Open the box up—let's see what's inside! Open up the hood so I can take a look at the engine.
4. Of an establishment, to begin operation for the first time. I hear there's a new movie theater opening up across town.
5. To open at the beginning of the business or work day. What time in the morning do you typically open up? My office building opens up at 7 AM, so I'll be able to get in early and make some tweaks before the meeting.
6. To fire or begin firing a gun (at someone). The troops opened up as soon as they saw the militants exit the building.
7. By extension (of meaning 4), to begin attacking, criticizing, or interrogating someone. The reporters opened up on the commissioner with a barrage of intense questions.
8. To speak candidly; to reveal one's inner thoughts or emotions. Often followed by "with/to (someone)." I've been trying to get Jeff to open up a bit, but he just likes to keep things to himself. You need to learn to open up to your wife, or your relationship is doomed for failure.
9. To become available or viable. The company is so massive that there are jobs opening up all the time. With recent changes in the legislation, that region is opening up as a potential new market.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
open up to something
to become more accepting of someone or something. Finally, he opened up to the suggestion that he should leave. Finally the boss opened up to the notion of Tom as a manager.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.