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cracking

American  
[krak-ing] / ˈkræk ɪŋ /

noun

  1. (in the distillation of petroleum or the like) the process of breaking down certain hydrocarbons into simpler ones of lower boiling points by means of excess heat, distillation under pressure, etc., in order to give a greater yield of low-boiling products than could be obtained by simple distillation.

adverb

  1. extremely; unusually.

    We saw a cracking good match at the stadium.

adjective

Informal.

  1. done with precision; smart.

    A cracking salute from the honor guard.

idioms

  1. get cracking. crack.

cracking British  
/ ˈkrækɪŋ /

adjective

  1. informal (prenominal) fast; vigorous (esp in the phrase a cracking pace )

  2. informal to start doing something quickly or do something with increased speed

"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

adverb

  1. informal first-class; excellent

    a cracking good match
"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

noun

  1. the process in which molecules are cracked, esp the oil-refining process in which heavy oils are broken down into hydrocarbons of lower molecular weight by heat or catalysis See also catalytic cracker

"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
cracking Scientific  
/ krăk′ĭng /

  1. The process of breaking down complex chemical compounds by heating them. Sometimes a catalyst is added to lower the amount of heat needed for the reaction. Cracking is used especially for breaking petroleum molecules into shorter molecules and to extract low-boiling fractions, such as gasoline, from petroleum.

  2. See also hydrocracking

Etymology

Origin of cracking

First recorded in 1250–1300; Middle English; crack, -ing 1, -ing 2

Vocabulary lists containing cracking

Organic Chemistry

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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.

“Thank you very much,” he said to the fans, his voice cracking.

From Los Angeles Times • Apr. 11, 2026

Leaps in AI model capabilities have come with concerns about hackers using such tools for figuring out passwords or cracking encryption meant to keep data safe.

From Barron's • Apr. 7, 2026

His bad-tempered outburst showed a different side of a man used to cracking jokes and charming even his critics.

From BBC • Apr. 3, 2026

Woods has grown comfortable with his aging, quasi-emeritus role, cracking wise about the sport’s up-and-comers and his various old man ailments.

From The Wall Street Journal • Mar. 29, 2026

She sprinkled a few drops of oil on the braid-hands and they startled awake, stretching and cracking their knuckles.

From "The Marvellers" by Dhonielle Clayton

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.