blow up

British  

verb

1. to explode or cause to explode

2. (tr) to increase the importance of (something)

   they blew the whole affair up

3. (intr) to come into consideration

   we lived well enough before this thing blew up

4. (intr) to come into existence with sudden force

   a storm had blown up

5. informal to lose one's temper (with a person)

6. informal (tr) to reprimand (someone)

7. informal (tr) to enlarge the size or detail of (a photograph)

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noun

1. an explosion

2. informal an enlarged photograph or part of a photograph

3. informal a fit of temper or argument

4. Also called: blowing up.  informal a reprimand

blow up Idioms  

1. Explode or cause to explode. For example, The squadron was told to blow up the bridge , or Jim was afraid his experiment would blow up the lab . The term is sometimes amplified, as in blow up in one's face . [Late 1500s]

2. Lose one's temper, as in I'm sorry I blew up at you . Mark Twain used this metaphor for an actual explosion in one of his letters (1871): “Redpath tells me to blow up. Here goes!” [ Colloquial ; second half of 1800s]

3. Inflate, fill with air, as in If you don't blow up those tires you're sure to have a flat . [Early 1400s]

4. Enlarge, especially a photograph, as in If we blow up this picture, you'll be able to make out the expressions on their faces . [c. 1930]

5. Exaggerate the importance of something or someone, as in Tom has a tendency to blow up his own role in the affair . This term applies the “inflate” of def. 3 to importance. It was used in this sense in England from the early 1500s to the 1700s, but then became obsolete there although it remains current in America.

6. Collapse, fail, as in Graduate-student marriages often blow up soon after the couple earn their degrees . [ Slang ; mid-1800s]

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Example Sentences

With “Ugly Baby” being your seventh special, are you ever running material by your family like hey, I’m about to blow up your spot?

From Los Angeles Times • May 6, 2026

If a migrant family worries that a medical shock, a job loss, or school fees could blow up their finances, the rational response is to bank cash.

From Barron's • Apr. 27, 2026

Even the principal can blow up the schedule.

From The Wall Street Journal • Apr. 27, 2026

My sore throat was gone, but speaking for more than 10 seconds made me lightheaded, as if I were trying to blow up a balloon simply by talking.

From Slate • Apr. 18, 2026

“It’s possible that the campuses are really going to blow up after this speech,” Nixon told his secretary.

From "Most Dangerous: Daniel Ellsberg and the Secret History of the Vietnam War" by Steve Sheinkin

Related Words

• burst
• crash
• detonation
• eruption
• explosion
• outbreak
• outburst
• volley