open up

Verb

open up (third-person singular simple present opens up, present participle opening up, simple past and past participle opened up)

1. (ambitransitive) To open.
   • Some vacancies have opened up due to retirements.
   • Open up the door!
2. (ambitransitive) To widen.
   • The corridor gradually opened up into a triangular room.
   • Much as one appreciates the beauty of these woodlands, it was good to learn that some discreet tree-felling may open up the view still further.1958 July, R. K. Kirkland, “Into the Mountains on the Festiniog Railway”, in Railway Magazine, page 453
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.1914, Ernest Bramah, Max Carrados
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) 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.1934, Henry G. Lamond, An Aviary on the Plains, Sydney: Angus and Robertson, page 211
   • Then we simply crawled onwards to Tebay, and not until well on to the 1 in 75 did the driver open up; the result was no greater drop than from 57 at Tebay to a sustained 40 m.p.h. up the last mile to Shap Summit.1957 August, Cecil J. Allen, “British Locomotive Practice and Performance”, in Railway Magazine, page 568
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.2015, Robert Barton, Acting: Onstage and Off, page 184

   Synonyms:

   cheat out

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