open up

verb opens up · opening up · opened up

1. ambitransitive To open. Some vacancies have opened up due to retirements.
2. ambitransitive To widen. The corridor gradually opened up into a triangular room.
3. transitive To bring up (a topic etc.). Mr Hollyer opens up three excellent reasons why this man might wish to dispose of his wife. If we accept the suggestion of poisoning—though we have only a jealous woman's suspicion for it—we add to the wish the determination.
4. ambitransitive To reveal (oneself); to share personal information about oneself; to become communicative. After three hours of questioning, he finally opened up.
5. intransitive To commence firing weapons. As the convoy entered the pass, we opened up on them with everything we had.
6. figuratively, intransitive, of the sky To rain. The sky has really opened up. I've never seen this much rain!
7. intransitive To berate; to begin shouting at or insulting someone or something. As soon as she saw him, she just opened up!
8. intransitive To begin running, driving, travelling, etc., at maximum (or faster) speed. The pigeon is moving as before with unhurried haste. [...] But it must be all out. If it wasn't, then it would open up and get away from that shadow of death behind it.
9. intransitive Synonym of cheat out (“to face or turn toward the audience more than would be natural”). In stage acting, we are frequently asked to cheat out to the audience by opening up our body positions so that we are something halfway between facing them and our partner.

   Similar: cheat out

10. intransitive Of wine: to develop its full flavor a short time after being uncorked and poured.