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Synonyms

open up

British  

verb

  1. (intr) to start firing a gun or guns

  2. (intr) to speak freely or without restraint

  3. informal (intr) (of a motor vehicle) to accelerate

  4. (tr) to render accessible

    the motorway opened up the remoter areas

  5. to make or become more exciting or lively

    the game opened up after half-time

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

open up Idioms  
  1. Spread out, unfold, as in A green valley opened up before us . [Early 1800s]

  2. Begin operation, as in The new store opens up next month . [Late 1700s]

  3. Begin firing, begin attacking, as in The artillery opened up at dawn , or, figuratively, The speaker opened up fiercely on the opposition . [1930s] Also see open fire .

  4. Speak freely and candidly, as in At last the witness opened up and told what happened . “ Colloquial ; c. 1920]

  5. Make an opening by cutting, as in The surgeon opened up the patient's chest .

  6. Become available or accessible, as in With new markets opening up all the time we hope to see our revenues increase dramatically . [Mid-1800s]

  7. Increase the speed of a vehicle, as in Let's see how fast the car will go if you open it up . [ Colloquial ; c. 1920]

  8. Open the door, let me (or us) in, as in Open up! This is the police . [Mid-1900s] Note that in all of these usages except def. 4 and 7, up serves as an intensifier, that is, it emphasizes the verb open .


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Homes have been evacuated after a sinkhole believed to be from an old mine opened up and swallowed a road sweeper.

From BBC

The opening up of Argentina’s nascent mortgage market is also expected to boost sales.

From The Wall Street Journal

People are being encouraged to open up about their mental health at events as part of Time to Talk Day 2026.

From BBC

"I was lucky to have friends about that I could talk to and that helped. I hadn't talked to anyone about it before then. I opened up."

From BBC

The six-part series will also see the singer open up about the pressures of fame, her decision to leave Little Mix in 2020 and the controversies that followed.

From BBC