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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.

Bloom, don’t simmer Spices and aromatics cooked briefly in fat open up quickly, creating depth in minutes rather than hours.

From Salon • Apr. 3, 2026

“When this conflict is over, the strait will open up naturally,” Trump said.

From Barron's • Apr. 2, 2026

The podcast, he says, is a space for him to open up more than he already has.

From Los Angeles Times • Apr. 1, 2026

"It was fun getting to open up," she remembers.

From BBC • Mar. 26, 2026

“I just wish he’d open up more and give me a chance,” I heard Ms. Newberry say.

From "Because of Mr. Terupt" by Rob Buyea

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.